Can't come during oral

So I'm new to the world of sex and sexual stuff. I'm still a virgin but I've done everything else: blowjobs, handjobs, been eaten out and fingered. The stuff that he does to me is great, but I can't cum :(

When I masturbate I never used fingers or touched myself, I would watch porn and squeeze my thighs. I've had AMAZING orgasms with this method.

I LOVE it when he fingers me with 2 or 3 fingers and licks my clit but because my legs are wide open I can't cum After he comes up for air (hahah xD) and rolls over, I turn on my side and squeeze my thighs... that's when I start orgasming a little (small contractions).

Can someone please give me some tips and/or explain what's going on?