Clit vs penetration???

How come when I stick my fingers in nothing happens?? Everyone seems to orgasm from penetration but to me it either hurts or I can't feel anything at all. I can only get off from clit stimulation, and I'm scared that when a guy wants to have sex and put his dick inside of me that I won't feel anything at all and I'll have to fake it. Any tips on how to get turned on by fingering/penetration, etc???