Bad headaches and really bad neck pain?

So one day I woke up with a really stiff neck, and it hasn't gone away, just gotten progressively worse. I hear crackling noises in the back of my head whenever I move my neck, like grinding noises... I've got my mum to mage it, and tried hot water bottles, ice, taken tablets, and hot bubble baths. I also get quite bad headaches and shoulder pain, I don't know if this is related? I've tried researching online and a lot of people have said it could be arthritis? But I've only just turned 15...? It used to be so unbearable that I would just go to bed to stop the pain, but I've sorta gotten used to it now... Thanks if you help :) xxx