Possible ASD - possibly not - nervous about asking for diagnosis

Hi, I've been wondering for a while if I might possibly be on the autistic spectrum.  Naturally, I've had a good look around the internet but found it to be pretty inconclusive.  I've done a couple of online Asperger tests, which seem to put me on the borderline - if that's a thing.

I often actively avoid having one-to-one conversations with people - particularly if there's a chance that it might go on for a long time.  I never know what to say when people ask those perfectly reasonable 'how's the job' or 'how's the family' type questions, and it would never occur to ask such questions back.  to me, small talk and chitchat are baffling things, to be avoided if at all possible.  Having said that, I've always thought I was quite good at reading people's facial expressions and 'getting the joke' and so on.  But on the other hand, I often find myself having a conversation with someone and thinking: "I have no idea what you're on about, and so I have no idea what to say next".  Also, I don't know if it's relevant, but in terms of jokes, I've always thought that practical jokes are entirely unfunny and essentially just mean.  I also struggle when people ask me verbally to do something.  I think I understand when they're speaking to me, but as soon as they've gone, it all just seems to fall out of my head.

I think I'm reasonably good at understanding how language works.  I don't usually take people too literally, although I will generally notice if there is an alternative, more literal sense to what they're saying.  for example, the media often refers to footballers being 'handed' a ban for committing some foul or something, and I always imagine them being literally handed something with the word 'ban' on it.  I've also noticed that people often assume some ulterior motive or hidden agenda when I ask them something, and I find myself wishing other people could just be a bit more literal-minded!

There have been occasions when people have thought I was being insensitive, and I often seek out time on my own, especially when at a large social or work-related gathering.  I used to have plenty of friends, but I realise now that that was largely a result of being thrown together, e.g. at school.  I have no idea how to go about making friends with people as an adult, and I'm only half-sure I want to.

I have some (what I think of as) minor rituals that I like to stick to, and what I used to think of as slightly OCD tendencies.  I don't have any obsessions, although long before I started wondering about autism, I came to realise that there are quite a few things that I quite like doing, but nothing that I really love doing.  And it really feels like it would do me good if there was something that I could truly immerse myself in.  I'm not sure about sensory sensitivity.  There are certainly some sounds that I find distracting/irritiating, but it's hard to know if it's more so for me than anyone else.

I hope it's OK to write all this stuff on this forum - it feels good to get it off my chest if nothing else.  I'd be really interested to know people's thoughts about what I've written.  I'm pretty nervous to start the process of asking for a formal diagnosis.  if I got such a diagnosis, I think it would explain a lot, but if I didn't, I'd still be left with all these problems with social interaction and communication, and then what?

Thanks for reading.