I was prescribed Bactrim for UTI and took two pills. Yesterday m...

I was prescribed Bactrim for UTI and took two pills. Yesterday morning I woke up with a rash on my upper back and forearms, and had headaches off and on all day. I also had some slight kidney pain, especially on my right side. I took that day's dose anyway, even though I was sure it was the Bactrim causing it. I woke up this morning and the rash had spread all down my torso and arms, front and back, and I am still having headaches. I also had a hard time sleeping last night, not because I was itching, but was restless. I have stopped taking the Bactrim and the doctor wants to prescribe a different antibiotic. I don't think I will take them unless the UTI comes back later.