I might be able to offer some help if only I had a clear idea of what you mean. Please clarify.

i agree with dancingdoc lack of detail does not help. maybe posting a detailed description of what you are asking so somebody can get back to you

There is ONLY ONE therapist here that could possibly answer the first question ....and that would be Carnac the Magnificent :D

I believe I know what he is talking about because I myself am going through the same thing. When he is touching and fooling around with my clitoris I come close to having an orgasm, but when I get the real serious feeling all over my body and my whole body starts shaking, I freeze up and ask him to stop...
any advice?!

Give yourself permission to enjoy sex!

This orgasm is good. Pleasure is good for you. Etc. etc. etc.
Stop tellign yourself no - just relax and relish it!