Sexual intercourse does trigger an UTI if sexual hygiene is not maintained. Also, if your husband had an active infection then, the chances of you getting it are also high.
Try taking syrup Citralka 2 tablespoons full in half a glass of water thrice daily for 2 days. Also drink plenty of fluids, especially cranberry juice. If the symptoms don’t subside in 2 days you may need a course of antibiotics.
A single episode of diarrhea
is not worrisome.
Get a urine routine done to rule out UTI.
Hope this helps.