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.