Why do my legs itch after wearing tight pants?

About 3 years ago, I sat on fiber glass at camp, but since them all of them have came out, but when ever I wear like skinny jeans, leggings, or tights, and even jeggings, my skin on the back of my legs (on my thighs, butt, legs), start to itch like crazy!! I don't have dry skin, and I know its not the fabric. Just PLEASE HELP!!! I'm in love with fashion, but theres alot of things that I can't wear because of this issue :(