14 and seriously ill!!!!!????!!!!!?

For the last year I have been taken seriously ill. I have been debilitated with exceusiating headaches, severe sensitivity to sunlight, off my food, bone and joint paint! I have been so tired and ill. I am missing crucial schooling for my GCSE's and I can't go outside without being dosed up on painkiller an sungles! I am currently going to physio for the joint and bone problems and have been going back to the hospital constantly but they still don't no what's wrong! I have been talking to them for ages and yet no diagnosis. Recently u have found a few small raised lumpy spots that are same colour as my skin unless I ich them. They are only on the upper of my arms about 5 or 6 on both and 2 in my face. Plz if anyone has any idea what is wrong plz suggest so u can suggest to my doctor why it might be I just need this to be over! It's ruining my life!