Why cant doctors find out whats wrong with me?

ive been having this rely bad lower abdominal pain on my right side,my right testicle is in pain if someone touches it and doctors cant find out whats wrong with me they toke the following test. i don't know the names but i can describe it. a machine that my body goes in and a circle thing spins around. that showed up negative then a ultrasound that came up negative as well then they did some blood test negative then some urine but i don't know how that came negative since i found some blood in there when i examined it. then came the x-ray negative as well. then came a piece of paper getting shoved up my butt negative then they came up with the conclusion that i am faking it but they did not say it like Ur faking it they said maybe there something going on with Ur head witch is another way of saying im faking it but im not i was about to jump out of bed and run out probably shouldn't mention that. sometimes the pain go so high that i feel like im going to die if anyone is having the same thing i am what do you do to make it better oh yea and there nothing wrong with my head i have no problem in life i got some rely cool friends i get As Bs and 2 Ds but i get those Ds cuz i dont like to work to hard