UTI during 2WW 5DPO

Amelia
I have a pretty bad UTI that developed @1DPO but I was hoping it would pass by flushing out my body... Nope it's now going to my kidney's.  I'm going to urgent care to get on antibiotics but I'm concerned about taking antibiotics causing a spontaneous miscarriage.  I have been showing positive signs that i could be pregnant but the symptoms could be coming from the UTI?  
Has anyone ever gone through this?