Would dvt pain come and go, or is it constant? normal d dimer and doppler ultrasound in the past month. pain still there, intermittent in calf + thigh

Unsure...: You can have a DVT without having any pain at all, and the pain can be intermittent. But, very reassuring that the d-dimer and ultrasound tests were negative. You can also watch the size of the calf that is hurting (measure it with tape measure compared to opposite leg at same level); if it is bigger, then it might be worth repeating the ultrasound. But it sounds like something else is the cause.

Not likely: All your studies suggest no dvt. Pain is pretty constant from DVT until some treatment is given. I favor musculoskeletal pain accounting for symptoms.

Pain: if your ultrasound is normal don't worry pain fro a dvt takes time to resolve perhaps use of a compression stocking would help