Heel pain

Anybody have any ideas about pain in my heel. There is no stress fracture as had x-ray, the only injury runners world talks about is calcaneal bursa. But i don't know. Symptoms are shrp pain when press the back of heel (bursa area). when running dull pain usually subsides once endorphins kick in. i had a few weeks off to try and reduce pain but this made it worse, exercise helps reduce the pain, for the rest of the day. Also putting strain on calf as suffering strains as leg compensates. Does anyone have any ideas. I use a neutral shoe with forefoot cushioning as tend to run on my toes.