Processing time / Anxiety and social encounters

Hi all, I wanted to run something by you as I couldn't find enough info about it and wondered if its just me or...

I struggle as I guess many of us do with social interactions, over the years I have learnt to look at least near someones face when I talk to them and have learnt appropriate responses in conversation that reflect a little of my personality. So I get by although it feels a little like its more just an act and not really me (not anything like how I would be when I picture a conversation in my head)

Where I really come unstuck is what I have been told is called 'processing time', in that if something someone has said is new to me or a surprise, I don't get to give the response I would have liked to when I reflect on the conversation later.  Or perhaps a better example would be when I was out with a friend, we were chatting and the tone had changed, I knew something was different and so I wasn't sure how to respond so I stayed quiet, they then apologised for snapping at me some minutes later I said it was fine but it left a weird tension for a while after.

So it takes me actually reflecting when I am on my own after the fact to fully take in what has been said to me, I feel like I miss lots of opportunities and often misrepresent myself, I will often end up feeling quite upset if I don't stop myself replaying the scene and thinking about how I might have made the other person feel.

Does anyone else experience life quite like this?  I feel like if I could re-do each day I would be prepared and I could be myself, as it is it just feels like everything ends up a wasted opportunity and I just play out a rehearsed version of myself.