The first thing is to report it to your supervisor and the Human Resources Dept. This is not legal advice, but it may be covered under workman's comp. Next is stay away from the heating pad. It appears that the muscles in your back are inflamed and heat will make it worse. The first 48 to 72 hours use nothing but ice packs 3-4x a day for 15-20 minutes. Do not put the ice directly on the skin, use a towel. Therapeutic ice packs can cause burns if not used properly. Hot baths with Epsom salts is okay to relieve soreness. After the first 2-3 days, use a contrast therapy of ice 15 min., heat 15 min., ice 15 min. 3x a day. Also, during the entire time, avoid sitting for extended periods. Walk and do light stretches, but not to the point of sharp pain. If this does not seem to show signs of improvement after the first 2 days, see your chiropractor.