Hi there, yes, it is very common for women to feel extra sensitive after orgasm and also to lose interest in sex. This also happens to men. It's best to avoid touching the clitoris directly for a while after orgasm because of how sensitive and "intense" it feels.

It may be best to wait a little while after your girlfriend has had an orgasm before you continue to have genital sex. Just enjoy that time with her pleasuring you and just touching each other elsewhere on your bodies until she feels ready to have sex again. Hope that helps.