Re-occurring UTI’S?!

Okay so I’ve just recently started having sex with my boyfriend and since then I got a UTI that I took antibiotics for and then small, reoccurring symptoms that come and go. We’re both very hygienic and don’t have any STI’S/STD’S. I took the doctors advice and pee before and after sex and we use condoms every time. Sometimes I get random abdomen pain, sometimes I get the usual UTI symptoms (burning when peeing, cloudy urine, itchiness, uncomfortable) and I just drink more water and take vitamins C and cranberry pills and it clears up, but how can I stop it from coming back? Is anyone else going through this?