I got pain in the left top part of my back what would it be?

Really hard to say: Without knowing your history & doing exam. Am concerned you mentioned hydrocodone since you don't know cause of pain & there are usually better drugs for musculoskeletal pain. Common causes of upper back pain are muscle tension, poor posture, deconditioning/lack of exercise, shoulder problems, etc. If pain persists, please see a doc. Use ice/heat, massage, iibuprofen/tylenol instead of hydrocodone.

Unknown: There is no way of knowing without an exam. That said, the most common cause of back pain is muscle strain.