You didn’t ask for feedback so please forgive me if I’m out of line. I would say go for it because you have been looking forward to it, and it will get you out of the house, which is potentially healing with regard to social anxiety. Also you can leave early if you’re feeling uncomfortable with the new people (which affects me, too).
I have learned from my regrets that it’s true what they say about regrets being more about what we didn’t do, than about what we did do that didn’t go well. I still isolate from time to time, so I know this is easier to say than to do.