In reference to your past post - if you have RA it might be that - I would definately ask for an MRI of the cervical area - you could have something going on in the disc in your neck. I have fibromyalgia; I'm not an expert, but it doesn't sound like FMS to me. A rheumatologist can check you for FMS. Good luck.
I'm sorry you are having so much trouble; you are too young! Well, I'm not a doctor and I don't really have a clue what to tell you, but here are a couple of thoughts: have you grown much in the last month or two? People have growth spurts at different times in their lives - I'm just wondering if you've recently grown an inch or two? If so,, maybe your body just hasn't had a chance to catch up? My other thought - you might ask your doctor if you should have an MRI of your neck. Maybe you injured your back/neck (a disc or something) somehow? I hope you get it figured out and are able to start back getting exercise. Good luck.
please look at my past posts.