Can't seem to orgasm.. ever..

Girls please help.. I'm 21 and have been sexually active for about 2 years now but I've yet to even come close to orgasming from sex. There was one time that we were just making out/grinding with clothes on that made me come close but that was it. I don't know if I'm doing something wrong or if there's something wrong with me but I'm happy to take suggestions and advice!