I just wanna know what an orgasm feels like 😩

I've been with my boyfriend for 4 years and lost my virginity to him. For some reason whenever we have sex I cannot cum.. I feel like something is wrong with me. I've tried every position possible and that doesn't seem to help either.. Am I doing something wrong, is this normal lol should I see a doctor or what?! I just need some advice on what to do. I love my man and I wanna know what it feels like already 😩