Sexual and orgasm advice needed

Awhile back sex wasn't as good for me my body just had a hard time getting use to it later I learned most women have this but now I've been with my boyfriend for almost 2 years and I love sex I have no problems anymore I'm producing more fluids and feeling good feelings but I have problems achieving a orgasm sometimes I feel like I have to pee and I know that's one sign but somehow that feeling is there but I can't relieve myself or sometimes I want to have a orgasm but can't and I do over think during sex how do I relax how do I have a orgasm and what are some things we can do to spice things up