Severe back pain and how to stop or help it stop hurting a little.?

ok so im been sleeping on a mattress for over a month but my back never hurt from it. i woke up about five days ago and i had a horrible muscle spasm and it hurt like crazy after that i been having small spasms on and off and my back aches and hurts endless when i sit down and lay down. i try ed to use muscle rub for it and then i try ed to take pain medicine like advil and it just wont stop hurting i even try ed the heating pad NOTHING! please help... :(