is it possible not to know....

everything i have read says that once you have an orgasm you’ll know. but is it possible to not know? i’ve been experiencing muscle contractions, cramping after sex or oral, and a build up but never a release. is it possible that i’m experiencing small orgasms? what confuses me is there is no feeling of pleasure or release associated with the contractions but after the contractions it’s like i am less sensitive and can’t build the pressure any higher. thanks for answering.