Orgasms

Okay ladies, I need your help. I've been with my boyfriend for 4 and a half years, the sex is amazing, so amazing in fact that my legs tremble so hard and I feel like I can't take anymore. With that being said, I've never had an orgasm in my entire life. I have never masturbated because I always felt gross, but recently I did try and it was good. I made my own legs shake, but there was no... release? I love having sex, but I just want to know if there's something wrong with me. Sometimes I get to the point where it feels like I might, but then I have to make him stop because there's this almost "tickling" sensation where it feels like I'm going to laugh. Idk, any help would be appreciated.

Thanks in advance!

*Update*

I haven't told him to stop for about a month or two now. There's still no release. When he continues through that tickle phase, i get sensitive and then it's like the feeling goes away. It still feels good, but there isn't a release (idk how else to describe it. it feels like a build up of feeling that needs to escape but can't). Also, idk who responded down there, but it wasn't me. I'm anonymous because I'm embarrassed that I can't get "there". He also does rub my clit. A LOT. haha that's where the tickling sensation comes in.