I was dusting yesterday and all of a sudden i got an enormous pain in my back and fell to my knees. It felt like a huge knot was in my back and i was unable to move from the floor for 6 hours. I was finally able to crawl to my bed, but i am unable to put any vertical weight on my spine. Pain relievers dont seem to help much either. But, I am able to lie comfortably on my back or side as long as  i dont move.
Your symptoms are most probably due to a spasm in para spinal muscles. These are muscles that lie on the other side of your spine. They must have become spasmodic when you were dusting the rugs. I would suggest you to take complete bed rest for a period of 1-2 days until the pain subsides. However, you can attend to your daily needs and keep it to minimum essential activity. You can also afford some relief using hot water compresses over that area for a period of 20 minutes every 3 hours. Since the pain relievers aren't helping, you should get prescription medications for a period of two weeks, for which you will need to see your physician.