I was prescribed an antibiotic for 3 days for a urinary tract infection and I am still experiencing symptoms after 2 days of taking it. What should I do?

Hello, I went to see a doctor for a urinary infection yesterday. She prescribed an antibiotic for 3 days. In the past I already had an infection and the 3 days of antibiotic was not enough. I told her about it but she still prescribed the antibiotic. After 2 days of antibiotics I still feel a discomfort and she told me to go back and see her if after 24hrs I still feel symptoms except that it's the weekend and the 1st everything is closed :/ I was wondering if I should go and see a pharmacist, can he prescribe me another antibiotic or should I take my pain and try to get an appointment after the day of the exhibition, thank you in advance

I only have one dose left for tonight and I still feel some discomfort but it's really light so I don't know if it's normal or not... I think I'll be able to wait after the leave as the symptoms are light for now but I'm wondering if I should go back to the doctor or if I can go to a pharmacist... I know that the doctor I saw had a durin culture done just in case the prescribed medication didn't work.

Thank you for your answer, I have not heard from my durin culture but finally the antibiotic seems to have worked because I have no more discomfort for the moment. I am crossing my fingers that it does not come back, thank you again.