Could be a combination of things, please see your doctor and tell them what you said here, so you can get this all cleared up and be healthy.
It could be anxiety but I think a visit to your dr for a physical is a good idea. Tell him/her your symptoms and also ask to have a full bloodwork up.
If everything comes back fine then it might help to ease your mind. I would then suggest you see a therapist to deal with the anxiety.
I hope everything works out well for you.