I was going out for Valentine's day and had a pain in my stomach all day. Ended up leaving work early to take painkillers, cancelling the night out, then having to go to A&E when I could stomach it no more. Turned out the scar from my appendicitis op 5 months earlier had stuck to my stomach wall and ended up having an emergency op.
I found out the result when I came round from the anaesthetic and was so groggy I thought I had dreamt it. Also on the plus side, I didn't spend a dime that Valentine's night.