Gastritis symptoms, upper back pain where i have a hump at my neck, neck pain, headaches, fatigue, could this all be stress, seen many docs too?!

Well: Lots going on here. So to diagnose you correctly each complaint must. be addressed. See your doctor for full exam and evaluation. This is where you start

Stress: Yes: stress can play a role in digestive issues, muscular pain/spasm. fatigue, anxiety, depression weight gain/loss etc. If your medical workup, including GI evaluation is otherwise normal, I suggest several sessions with a clinical psychotherapist to address stress issues.