Urinary tract infection

Patient: Hi last week i have been suffered from itching and burning sensation in the vagina and frequent urge to urinate.i then drank lot of water and cranberry juice and got relieved from the above discomfort.later i went to se a docter who prescribed me nitrofurantn and phenazopyrid. i came to know that phenazopyrid is used to relive pain but now i donot have any symtomps of pain.Now i am in a confusion whether to use that medicine or not