Suggest Treatment For Severe Pain In Back Along With Nausea And Chills

Last Sunday I developed severe pain on the right side of my back. I could barely stand or move. It was accompanied by nausea, vomiting, alternating chills/sweats, and total loss of appetite. Frequency and degree of urination increased dramatically. I spent the next four days in bed on a heating pad, sipping water occasionally (the only thing I could keep down) and taking lots of pain pills. Within the first 36 hours I lost all the swelling I have had in my ankles for the past 25 years, as well as 7 pounds. Yesterday (Thursday) I was able to keep down some chicken noodle soup and some ginger ale, and the pain had lessened to where I could stand to be upright for a short while. The pain is still there, but not anywhere near as severe....it just won t go away. today, the longer I am up, the more severe the pain returns. When I move around I break out in the sweats. When I lie down on the heating pad I get cold. Does this sound like something that might require immediate medical attention (I am very limited on funds), or could it be something that will pass with time if I do certain things....suggestions would be welcome. What do you think?