I have a fidget spinner ring that's kinda discreet so I can stim. Maybe you can get some loop earplugs to dampen the noise. I also used to bring this tincture and put a few droppers full into water and drink that. Kava is in it and that specifically can soothe your nerves and is known to help people loosen up/be more sociable, but you don't get drunk or high, it's just an herbal tincture. Its a very...strong taste though lol. Or maybe, it could help if you could find a bar arcade, play pool, or do some kind of activity while out with them at the bar. being able to focus on a game or task might help everything else to feel less intense.

Also, there is nothing wrong with just going for a short time and leaving when you know you're at your max!