Bactrim Severe Sunburn, Burning Sensation, Lower Chest, Pain Med, 6th Day

I was prescribed Bactrim for a UTI and felt worse after starting the Bactrim...headaches, chills, aching all over my body. On the 6th day of taking Bactrim I woke up with a burning sensation on my back, by the 7th day the burning sensation had spread around to my lower chest. the burning sensation is what you would have if you had a severe sunburn, but no redness!! It's bizarre. I told the doctor about what was going on and he said to continue the Bactrim because he didn't think my symptoms sounded like a drug reaction. I strongly disagree, so I stopped taking the Bactrim with only 2 days of medicine left. I'm now about 36 hours medicine free but from what I understand, Bactrim has a 60 hour half-life so I guess I'm still under the influence to some extent. I still have the burning sensation on my back, which makes clothing almost unbearable and sleeping isn't doable without some type of pain med to get me past the pain....Just wondering if anyone else has had this type of reaction to the Bactrim experience. I know I'll never take that drug again, for sure.