Tough UTI and kidney stones

Patient: I have been struggling with really strong ammonia smelling urine for almost 4 months. It is not every time I use the restroom. I go normally most of the time, but sometimes I feel a great urgency to go and that is when it is really really strong. It happens about 3 times a day. I was tested for an infection and it came back negative until I asked them to do a catheter, then it came back that I had e coli. I took amoxo clav and it helped until the prescription was over and then it came back. I took another round and it did the same thing. After that my urologist decided to blast some kidney stones thinking it might be causing infections. I was put on a stronger dose of amoxo clav for a longer period. It helped while I was on it and then it came back a day after I was done with the prescription. I called him to see if they had tested the bacteria to see if it was resistant, but he said that my culture had come back clean during my pre op for the lithrotripsy. It is just a strange infection to me because it does’t always show up on the culture and it doesn’t alway smell and sting. I notice a significant difference in my urgency to urinate when it is foul smelling. I just had a baby via c section about 3 week before I started struggling with this. I am just wanting to know if this is normal and what I should do for it.

Symptoms: Strong ammonia smelling urine.