I wouldn't go full tilt on the painkillers. They are just masking the symptoms. You are liable to have "rebound" pain when you come off them. I don't think you r doctor is competent based on this medication choice. It shows he is choosing not to treat the cause of your problem, just the symptoms. And it sounds like he is doing it in an irresponsible way. Your fatigue is your brain/body telling you to slow down. I experience it daily.

As for your headaches, have you tried any injections? Other therapies besides medication? You need to have your neck and evaluated to see if there is soft tissue damage. Many here will tell you that your best bet is rest. That is largely true. Rest and try to build up to certain tolerances for activity. I am young like you and it is incredibly difficult to do this every day. But the alternative will make you worse.