Can't orgasm?

My boyfriend of 2 years and I have great sex, I've only ever been with him and I don't masturbate. Just can't get the hang of it and it's not really something I'm interested in. However, since I lost my virginity I've been having sex for a year now and I've yet to orgasm. I'm not sure why because the sex feels incredible and he's doing everything right, but it never just goes over the edge to O town I guess. I've never orgasmed before by hand or anything so I don't know what works but do any of you have tips for what gets you there?