Was doing DB shoulder presses.
I was young, so I threw around the big weights. Had the 110's in each hand. Kicked them up, did my reps, then went to put them down. But I was tired, and wanted to be a big boss. So I let them drop from shoulder height to the ground.
Which would have made a sweet boom. Except my left toe broke the fall of one of the dumbells.
It was the most excruciating gym pain I've ever had. For some odd reason, the toe did not explode, though it felt like it should have. It just killed the toenail, made it bleed like a stuck pig, etc...
I just sat on the chair, rocked back and forth for a while, and let the tears stream down as I bit my lip. A few minutes later I limped thru the rest of my workout, suffered the longest walk home, and went to bed to try and sleep it off.