I am 21 and I have severe burning while urinating

Patient: I am 21 and I have severe burning while urinating and abdominal pain while urinating. Feels exactly like a uti but uti home test is negative. I recently was prescribed metronidazole (flagyl) for trich after my ex of 3 years cheated on me (which has been my only sex partner) I wanted to be safe so I got a Pap smear and all other stds were negative. I took all the meds and on the 5th day I had protected sex with the same partner. Could this be why I’m getting the symptoms back? Even though it was protected ? Or could it be something else??

Doctor: Hi,Thanks for the query.I understand your concern.If there was no direct contact between genital secretions t he possibility of transmission of infection is less.Better to go for urine culture and sensitivity to find out the possibility of infection and take treatment accordingly.Intercourse should be avoided till the completion of treatment and both partners should be treated simultaneously to prevent cross infections.Take care