Should i take antibiotics if i have a mild UTI

The other day I was feeling very tired, dizzy, and actually fainted, so I went to the ER. The tests showed I have a mild UTI, but I didn’t have any symptoms, and the doctor didn’t prescribe antibiotics since I had no pain while peeing. I’m still feeling very tired and unwell, and I’m concerned it might get worse if I don’t take antibiotics.

What should i do??