I've Been Taking A Prescription Meloxicam 15 Mgs For Over

I've been taking a prescription Meloxicam 15 mgs for over a year. I don't feel like it is helping much because I still feel stiff and sore achy all the time, but if I don't take it It gets worse. Should I ask my doctor more a larger mil gram or do you suggest a different medicine. My doctor is not sure if it is fibromyalgia or not.