Everytime after my boyfriend cums in me, a couple days later my urine smells bad for like a week with no pain. Is it a UTI that I keep getting?

Probably not..., but. In your clinical setting, no discomfort in urination suggests less possible to have uti. But to confirm if UTI does exist, go to get urinalysis with the carefully collected mid-stream urine specimen to avoid contamination which is common. If urinalysis is normal, i would not worry about it and leave it alone. Nonethelss, go to see a professional if in doubt.