Can’t orgasm?

So when I masturbate I normally just rub my clit. I get to the point where my legs start shaking, my heart rate increases, I feel warm, etc, but I don’t think I’ve ever actually orgasmed. After masturbating for a bit, and hanging the leg twitches and stuff, all of a sudden I don’t feel good anymore. Like I don’t feel anything when I touch my clit. I never get to a point where it feels like a release, it’s just build up and then it’s done. Does anyone have a suggestion on what I should do/ know what’s happening?