foot pain

back in late may 2007 had no foot pain. In early june was doing leg exercises where you stand on one foot and holding ankle of other foot you pull up and back so as to touch heel to lower back.Next morning had severe pain in buttocks on side of leg pull.When taking shower that morning had to bend down on pain side to take pressure off buttock..Although buttock pain subsided i developed pain along bottom of foot from heel to ball of foot. Eventually progressed to top fo foot and toes.Unable to walk barefoot due to pain.Went for foot therapy. No help.went from shoes with about 2 inch heels to sneakers.Shortly thereafter similar pain developed in other foot.Although i had no back problems at that time, is it possibly back related due to nature of initial pain(buttock area).or did i do some damage to my foot?.Don't understand why it went to other foot.Went to several foot doctors and an orthapedist,physiatrist,and spinal surgeon. Metatarslgia,and morton's neuroma were ruled out.Can't seem to get a definitive diagnosis.worst pain is in heel and top of foot (pain and burning),top and bottom of big toe and big toe joint.Wear orthotics.To me this is very perplexing and upsetting.Some suggested back related while others were not sure.Thank you for any informatiopn you may provide...