how do I not misunderstand other people's intentions and then going off on one?

Assume that their motives are good despite how you feel.  It’s okay to be wrong as a result of a disorder like ASD.  We are right about our special interest. 

There are two things I can think of in regards to how, as you put it, "sticking up for yourself causes drama".

Either, people like to shift all of the blame onto you, especially if they known that they may be able to use your diagnosis as a scape goat for their poor behaviour towards you in a "they are the one with problems, therefore I can't be the problem" sort of attitude, or the other option is that you have to reflect on how you are sticking up for yourself.

There is nothing wrong with sticking up for yourself at all, but there are definitely more positive and more negative ways that you can carry it out. Personally, I find that doing anything to make the other person go on the defensive very quickly, such as snapping at them, tends to end in conflict.

That being said, of course, it depends on what the situation requires. There are certainly situations/ people who deserve to have a verbal boot up the butt sometimes.

yeah, I guess I could ask rather than just getting angry and guessing

I've been told it's always me who misunderstands and it's one sided and I create drama with it apparently especially with people I know I just don't know how sticking up for myself is causing "drama" 

I'm on a low dose Risperidone now which is making me less agitated so I'm gonna see how that goes

I get this quite a bit. I have also been in situations with my boyfriend (who I obviously would never want to hurt intentionally) where he is upset about something and I don't realise and he gets upset even more because I haven't realised that he was hurt initially.

I think this is an issue that is going to take some time and work, but if possible the first step might be to speak to those you are close to/ feel comfortable with about your difficulties and just explain that it comes from a place of guilt as well. Even if there are people you don't feel comfortable disclosing your diagnosis with, if you find yourself in a conversation with them and it's going down a route you don't like then you can just ask for clarification. There is nothing wrong with just asking and it doesn't "out" you as there are many people who aren't neurotypical who need clarification to.

These problems tend to be more often/ severe with autistics, but that doesn't mean other people don't experience misunderstandings as well so please don't think that you'll come across in any particular way if you just ask for clarity.

Hope I've helped a little bit :)

Would you be able to ask them to clarify what they mean and then say how their wording came across. 

You would have two outcomes:

1. You'd know they intended their position. You can be angry but you wouldn;t punish yourself for misunderstanding.

2. They clear up it wasn;t intended that way and you are both happy after a bit of awkwardness.

If there is a no. 3. it may be worth seeking assistance for yourself in a positive way.

Amen.

You will not be able to understand another Person untill 
you understand Yourself   

no worries :D yeah it's usually when I'm walking away from the person when I start to react and it's a bit embarrassing that I'm shouting at myself while walking down the street fortunately I've never had anyone react to me 

I think I also get angry because I think they're taking advantage of me being vulnerable so they think they can talk to me like that but then I get told it's just a misunderstanding and I read it wrong and I feel so guilty afterwards and I don't live on my own so I end up being loud and get shouted at which gets me in to arguments

not a bad idea I could just ask them, sometimes it does end up like that sometimes and I'll apologise for the misunderstanding thank you for the advice 

Sorry, I didn't read the hurling insults and going angry in the street as being the same thing. 

Do you feel like asking them if they're upset or whatever would be doable? Or if that feels like too much of a huge deal, you could try just a quick "sorry, I didn't mean..." and they'll quickly jump in to correct you if everything was cool after all.

Jordan
Check Anglia Autism, if you are in the correct county you can apply  for an ASD Alert card.
Got mine a while back.
The card states " ATTENTION POLICE/ EMERGENCY SERVICES "
On the back it states your name and two contact details.
Sadly,i have had to use it a couple of times when certain People P...S me off.

you are right that I need to work on my response, I'm just trying to defend myself but I'm just hurting myself in the long run as can get me in to fights

I don't yell directly at them, I yell at myself later on after thinking of their response going over it in my head, and not saying anything to them

Well Jordan, if you are anything like me, then the thing you describe is simply a fact of life.  It happens with me, sometimes dramatically, sometimes on the down-low........but if definitely happens to me on occasion, no matter how hard I try to avoid it.

Needless to say, I do try and do everything I can to minimise how often it happens.....and I do that by asking lots of questions and making statements that I ask people to confirm or deny.  It can weird people out - you can see them thinking "are you a simpleton or something".....but I do find it's far easier to discover that I'm off down the wrong track as early as possible.

I tend to recount someones story or statement back to them with a "so that must have been tricky / complex / exciting / sad etc".....often they will look at me - blink - and say something like "no mate, I'm only joking obviously" or similar.

I find misunderstanding to be a fact of my life.

I don't think you'll ever be able to know for sure how they feel about it, but you can work on your response.

I think you need to separate out those two issues, because the misreading isn't the problem; it's jumping from thinking they might be upset to yelling at them. 

I get you.
That's  exactly why i am Billy no Mates.
Nobody gets me either.

Research facial expression, body language and tone of voice. While autistics have difficulties recognising these things subconsciously like neurotypicals do, they can be consciously learned, I did.