My husband is having severe back pain that is immobilizing him. It started at 3:30 pm yesterday when he was stretching, touching his toes and it suddenly spasmed to where he ended up on the floor. He can get up to pee but has not done so very much. He has mostly been resting, using Motrin but is still in constant pain. He has used a heating pad that has herbs in it and managed to take a bath with Epsom salts earlier. Normally he is a very healthy person who stretches and exercised every day. The same symptoms occurred at Easter but not quite as bad. It went away eventually after a few days. Any idea what it could be and what to do to help relieve the pain?