Rare disease???

are there any names for a problem where your knees hurt often and your get sharp pains in your body at random times and your only 15?

I am 15 and I get these weird pains in my knees it hurts to walk sometimes I notice I get them when my legs are crossed and I go to getr up but I also get sharp pains in my chest and arms and I have to stop doing whatever it is im doing, i dont do sports, ive been to the doctors theyve known about it for about 2 years and still dont know what it is is there any rare disease or something that i might have and like a week ago I got this really bad pain in my arm, it kind of felt like i got a shot but i didnt and nothing touched me so i dont know what it is

Knee pain could be anything. Do you play sports? You could have sprains/strains, tendonitis, torn meniscus. Are you growing? If you are worried, go see your doctor. Probably not a rare disease.

see an orthopedic doctor

growing pains

I know you are still growing at age 15 and this may contribute to pains in your young body.....why would you think you have a rare disease my friend.......I think we need to have an annual check so you won't worry your young mind into anything that will upset you.....luv kara