What Causes Burning Sensation In Feet And Tailbone?

For months now my husband has been having these spells where he experiences discomfort in his intestines/colon, elevated BP, Pulse, lightheadedness and his breathing gets labored. Sometimes they come after a BM. No constipation, No diarrhea. He also has burning in his tailbone and feet with an occassional weakness in the leg. All of his lab work, xrays have come back normal. Could this be neurological? He's 55, 5'7, 140 lbs, The symptoms seem to ease up after drinking lots and lots of water.