Weird questions.....?

Ok so 1. I heard that sleeping with a bra on gives you cancer. Is that true??? I sleep with my bra on EVERY single night because I just feel more comfortable that way. And 2......is it weird to trim ur pube hair? I did...am I the only one? I didn't do that just cuz I wanted to feel ike a kid again, only because long hair down there feels really gross to me. And it just bugs the livin daylights out of me. And last, I started my period...ehh....roughly 2 and a half years ago. And every month when I get it, I feel so uncomfortable and really can't stand it. At gym, I run the mile slowly because I'm scared I might leak, or I'm not as atheltic, and really dread going to ballet cl because you have to stretch your whole body and stuff. Also, I'm really scared because I'm going to a concert {Not saying whos because you might throw not serious answers at me} but I'm going to that concert around the time I usually get my period and I'm really scared I might get it the day I go. I have to travel in the car and stuff and I'm sure I'm going to be jumping up and down. Is there any way I can feel more comfortable about my self? And I tried tampons, but that only made things worst. I really don't know why though! I guess I just don't like the feeling of something being inside of me. I hate tampons. Do you have any advice? About how I can be more comfortable? Please only serious answers. I'd appreciate that.