I have itchy and frequent urinate for a week. Now I have sharp pain in left lower back. Does yeast infection cause the pain or sth else?
Something else. Yeast infection, limited to the vulva and vagina, is not likely to cause back pain. You may have an associated uti, but the history you provide is too sparse and you also need to be examined. See a doctor soon, and hope you are better in a short time thereafter.
I have itchy, frequent urinate. Negative uti, waiting for result for yeast infection. I feel occasional pain on left low back. Is it kidney infection?
No. You had negative ua I'm presuming by your negative UTI statement, essentially ruling out a kidney infection as kidney infections commonly ascend from the bladder.
Recently had uti. Now have white sediment & chemical-smelling urine & burning during sex. My partner says he now has itchy genitalia. Yeast infection?
Antibiotic use? If you took or are taking an antibiotic, then this may be normal. A yeast infection is not uncommon for the female that is being treated but not the male.