Autism or anxiety ? New adult

hi all, ive recently discovered the world of autism due to my son having Problems at school. ( last year or so)  He has been diagnosed with selective mutism but not autism. This has made me question my own problems and history.

im 32 with two children.  I have a history of anxiety and have always struggled socially.   I am wondering if my problems are autism related rather then anxiety and how do I tell the difference?   I scored 39 on the AQ test. I do not have any close Friends.  I struggle with new places and people. I always dread family occasions etc.  now my sons are both at school I also struggle with interacting with teachers/ parents.  I try and stay positive but so far I have not managed to make mum friends. I feel as though I have missed something constantly.. Plus if i ever get into a conversation I find it difficulty to know what to say / when to say it.  Is this just anxiety ? I sometimes say things that I think I should say because I've learnt over the years stock phrases if you like. 

Any advice much appreciated.  I'm not sure i could visit my GP about this but it is becoming increasingly difficult day to day. I'm also worried about thr impact this will have on my children because they are getting older and are going to realise that mum doesn't have friends / talk a lot to people. Thanks