Why is hard to orgasm...?

Hey ladies is it hard for u to have a orgasm? It's so hard for me to feel anything with my partner....he is the 3rd person I've been with it feel good with him but it's very rare when I have a orgasm.....? I love sex and I love to feel the D inside of me but I don't know what's going on....I have tried oils I have my cookie pierced and all and till it's hard...plz help has this ever happen to you? How u deal with it if it has has happened to u.