Orgasms.

Alright so I'm 18, I've been having sex for almost 5 months now and the guy is amazing, his everything is legit perfect with like a 7.5 inch dick and there was one more and the other one eats out like a god but damn I DONT ORGASM. Even when I'm just masturbating it takes me like 17 minutes to come. I know it hasn't been too long since I've lost it but it's just frustrating that I don't come at all during sex despite the fact that I love it so much. Is there anything possibly wrong with me? Or any way I can make this any better for myself?