I started trt a year or so ago and I've never injected this far back, but noticed a couple days after one injection I had a dark area on my mid/lower hamstring. It hurt a bit and as he says went on it started hurting worse and worse. Of course I'm an idiot and just delt with it. After a couple weeks there was no more pain and it went down in size a bit. Like I said about I always do quad injections but the bruise appeared on my hamstring. Could it be a cyst of some kind? Anyone ever had anything like this before? It's at least 4 inches from any injection I've ever done. Like I said it doesn't hurt anymore at all but maybe I should get it checked out?