Bactrim and mid back pain

I began taking bactrim for a UTI and by the first night I had diarrhea, persistent chills, fever (as high as 102.8), headache, severe lower back and mid back pain, everything pretty much described here. When I called the doctor they said it was related to my uti and that i needed to come back in to be re-evaluated. However I don't have insurance and I didn't have the money to come in. I ended up spending most of the afternoon in the hospital for them to tell me there was nothing wrong with me and all they could give me was percocet to ease the pain and "cruddy" feeling. The day after I stopped taking bactrim, I woke up with small red patches on my arms. The day after that I woke up with a sunburn like rash all over my arms and knees. I pray that this goes away soon!