Well it's not just a sunburn that made me feel like my insides were on fire. When I had the first ESR test done, I had previously all week suffered with kidney pain, that saturday went to burning really bad, sunday it attacks my bladder and causes severe pain there, the burning stops sunday night. My urine test was clear the following day but it did show an abnormal amount of bacteria (many), & amorphous sediment & crystals. Maybe it was indicating a UTI was previously present?? I know without questionable doubt I had a kidney and bladder infection prior to the test. The rheumatologist did not treat this or give me my results, though I have them now. I went on to having difficulty urinating, or not being able to urinate at all, the pain continued in my kidneys and bladder, and I did not get over this until I went to a clinic and got an antibiotic. ESR 5. So it raises in case of infections? I don't think so, no more than I think it will raise in mild inflammation in your muscles and joints. And it is extremely unfair that a doctor would judge whether or not someone has a connective tissue disorder based on this stupid test. I have both muscle and joint pains, however I do not swell and the pain is not evident to the human eye, that is why I think my inflammation is mild, the pain however is far from mild. I hurt constantly.