Ok So Here's My Story, My Gf Had Moved Into

ok so here's my story, my gf had moved into this trailer and decided to get a cat and the cat had fleas, got flea treatment and a flea collar for the cat and didn't think nothing of the fleas, since they bite. well everytime I went to visit my gf, we had unprotected intercourse, we have been for 5 years, and just 3 weeks ago I started to notices these bumps all over the inside of my thighs. I didn't think nothing of it as well and maybe it was from the fleas biting there. well just last week, I started to get bumps on my penis, quite a few of them, and there's a purple spot below the head, and all these bumps are very itchy at night(just my legs). then I start to get the bumps on my arms, my hands, my feet, my back, my stomach, my chest, and my lower neck. I really don't know if it is scabies, or flea bites, or bedbug bites, or an allergic reaction to something, or some kind of std. all I know is the bumps have tiny holes in the middle of each one like a mosquito bite, and then it crusts over as a scab. it itches all night long and I just cannot sleep. please help me figure this out.