ok so here is the story: i was playfully wrestling one of my friends and she pinched my dick skin and in the pubic area skin and twisted and it really hurt and the next day i woke up and there was a bump on the lower left side of my penis shaft that looked like a white head zit at first. It wouldn't pop and i left it and couple days later it has now turned black. It looks like a wart that got zapped of by a dermatologist. I need answers? could it be an std? i havent had sex in a few months. Could it be a blood blister?