Tall bar stool got pulled out just as I was hopping up onto it. Went backwards, head-first into the concrete floor, knocking me out. The guy was trying to be nice by pulling out the bar stool for me but that wasn't what I was expecting so the timing couldn't have been worse.
It took right at six weeks to be able to function normally again. And even a drink of alcohol would give me a headache.
It had been a very fun night up until that point.