I did not remember I had got any injury in my back earlier, but now a day I am feeling heavy pain in my back specially in the evening. I am feeling trouble to stand if it is more than 5 minutes and also feeling trouble to carry weights. Please help me.

It needs to be investigated. Investigations advised - hb, tlc, dlc, esr, sugar f & pp, uric acid, vit d3 urine r/e x ray of the affected part. Anyway you may try- sleep on a hard bed with soft bedding on it. Spring beds, folding beds or thick mattress are harmful use no pillow under the head. Do hot fomentation. Paracetamol 250 mg od & sos x 5 days. Caldikind plus 1tab od x10. Do neck back knee & general exercises. It may have to be further investigated. Make sure you are not allergic to any of the medicines you are going to take. If it does not give relief in 4-5 days, inform.