Help!! There's something seriously wrong with me!?

Okay,so! I'm only thirteen (female) and First of all i had broken aches on my feet! Then I had one leg longer then the other but only by an inch! Then I have reflux problems! Now I have stomach ache every day and I have back ach which differs from place to place (including lower back, shoulders and neck) I once cricked my neck when I was ten and now it stiffens up twice a month! The doctors all keep saying "it's growing pains!" then they say "leave it 6 month and see how it gose!" then they say "it's you posture!" when I look around and I'm sat up straiter then the doctor! I'm sick of this! Once I was told I would get a letter telling me to come have a CT scan and it would arrive within 1week! 3weeks later it hadn't shown we rang up the hospital and they said "oh yes sorry it's just on the desk I'll send it first class!" but it still didn't come! Until we rang again and then it came! I mean what's with that!!!!!!!!!!!!!! So can any one point out any tips please do! Oh yeah I have had trubles with my back since I was 10 but no one knows what's up with me! And im starting to think i crazy!