Random back pain.........?

I work as a receptionist and im sitting down alot. 2 months ago I had this really bad back pain. it was hard to move and bend. my doctor was perplexed but he immediately said it was acute lumbar strain. he gave me some flexor (sp) for muscle relaxant. Also Todar(sp) shot. It started to get intermittant. For a week I already had a cold and my back pain started the first day of my period. but I never had back pain I always had cramps. My cramps did not start immediately but after a few days it came. It was horrible. Back pain cold and cramps. It didnt go away after my period and i went to the doctor 3 days later and they did an x ray. after that I had blood work of liver kidney and a bunch of others. im borderline anemic for a moment i guess untill i eat healthier my 3rd doc said. my second doctor gave me heat treatment, mage and stretched me out on a machine. i was still taking the pills for the 3 days and I stopped andit went away. after a week after i finished taking the pill. I am overweight. They gave me a pee test the last day of my period. period stopped that morning. doc said no uti.nurse said it looked like it was before doctor left and came back. what was it you think?