I felt like the beginnings of a uti. it had been almost 2 weeks of frequency, pain when urinating but for the last week my back is hurting very bad i think its due to a kidney infection. im on antibiotics but i really thought it would be better?

Back pain may suggest the infection has spread up into your kidneys. Discuss with your local Drs. Now would be a good time.

Work up will be needed. Back pain is no longer in the confines of a simple UTI and has to be investigated promptly as conditions such as a kidney stone, a spreading infection to the kidney or unrelated causes will have to be ruled out. Not a good time to self diagnose, see your doc.