How to orgasm?

Hi! I enjoy touching myself, and I've been doing it for quite some time, but I never seem to be able to orgasm. I've tried fingering and clit stimulation, but I'm not able to orgasm. I have never orgasmed before, and only recently started "messing around" with my boyfriend. I'm not ready to have oral or sex yet though. When he touches me I feel the same kind of pleasure, but I'm never able to reach orgasm. But, we usually only have ten minutes max, because my mother is very strict :) I think if we had more time, I could cum, but for right now I'd like to know some helpful hints for orgasming? I have a lot of tension built up, lol, and usually it just fades away after a couple of days, but I would like to be able to take care of myself :) Thanks!