i need to know what it is im experiencing?

i am 22 years old female and have been sexually active since i was 15 years of age, my first orgasm was by myself which i tried in the toilet at the age 18. so i can orgasm whenever i want or with whoever im with. but one feeling i get i cant put a name to it, and for me its better than having an orgasm but no liquid comes out, nothing at all, it started when i was 19 years old, me and my bf at that time were having sex, and suddenly when i think im about to come, i get a sense of relief, as if i just had an orgasm but i didn't squirt and nothing came out so we carried on having sex. iv been with my boyfriend now for 2 years and to me im still cumming and loving sex but hes starting to get concerns that he cant satisfy me because im not squirting.i explained i most defiantly am, i even get that tingly sensation afterwards, my body even starts to twitch, but he wont believe me, so i need to know what it is im experiencing? or whats its called? it can happen when i dont control it