I have had mild knee and hip pain that has increased but xray is "normal" . what should i do next? no answer from dr. as to what might be wrong

Muscle or ligament: If the bones are ok (x-ray is normal) it could be something like a muscle pull of more likely ligament or tendon inflammation. See a sports doctor, sometimes an orthopedist or physiatrist.

Accurate diagnosis: Normal x-rays should not necessarily prevent a physician from making an accurate diagnosis. Treatment such as physical therapy, bracing, medications or injections can sometimes be diagnostic tools while also being therapeutic. Advanced imaging such as MRI can also be helpful when the diagnosis is in doubt. Finally, if your physician seems to be stumped, then obtaining a 2nd opinion is reasonable.