What Causes Severe Backache?

I have been having back pains (mostly around my mid to lower back area) for about 3-4 weeks. It gets worse when I lay down or try to sleep. Recently it has gotten worse ( a 9 out of 10 when it comes to pain). Now my stomach ( intestines ) also ache/hurt. After putting some thought into, it seems I may have had trouble with my stomach from the beginning. It just wasn t predominant . I have gone to urgent care and then followed up with a doctor s visit (when it appeared to just be my back giving me trouble). I was given ibprofen and Flexeril (generic). It does not appear to be working. I am having a horrible time at trying to get some rest and or sleep. The odd part is that during the day, while working my symptoms are bearable at times maybe even unnoticeable (until i eat ). I do not know what to do until I can get in to see the doctor again. Any suggestions on what I can do for relief or what may be causing my pain? I do not believe it is a muscle related injury or don t remember doing anything that may have caused one. Please help! Any suggestions would be greatly appreciated. Sincerely in Pain.