Clomid and UTI

Hazel
I get cystitis on a fairly regular basis (at least twice a year)
When I was first prescribed Clomid I was told to keep an eye out for urine retention. I got cystitis beginning December and was prescribed amoxicillin but its back again. I've taken over the counter cystitis drink stuff (GP surgery closed over bank holiday) but I'm staring to feel sick now. 
Gonna book a GP app for the morning to get another round of antibiotics but I'm wondering if the symptoms I'm getting are linked to the Clomid (50mg) or if it's just from lots of BD
Can any one tell me if their Dr's told them to look out for unrine retention/UTI's and what it could be a sign of?