I'm definitely leaning towards a horse fly. Dude they fucking hurt like a bitch. Put some topical hydrocortisone cream or benadryl cream.
Here are some bites, looks the same as the shit you got.
I also just spent two days reading this thread from start to finish. I knew KIR was the don when he removed his own cyst but this is next level. Best thread on this forum hands down. Check your pm's homie, I got stuff for ya!