All day today my arm has been hurting. What's wrong with it and what can I do to stop it?

Also my shoulder muscle hurts. My bookbag is really heavy and I sleep on my arms.

It's probably because of your bookbag. How much do you carry in your bookbag everyday?

Also, do you use a messenger bag or an actual backpack you carry on your back? Too much weight on one arm could be causing the pain.

It could also be a cramp from sleeping on your arms. Maybe change the way you sleep for a couple days?

Hope this helps!

I have an actual backpack I carry on my back. It's hard not to sleep on my arms I try but I always end up lying on them. But you're probably right thanks