I Have PMR. My Internal Physician Gave Me Predisone 20

I have PMR. My internal Physician gave me predisone 20 daily for pain. He also gave me naproxen. After taking the predisone my pain was relieved so I stopped the steroid and then began the naproxen. However, after taking a few naproxen, I had to stop it due to the headaches. Is this the beginning of GCA due to PMR or is it headache rebound due to the amount of napoxen I was taking?