Had sex in bath (fingering and protected vaginal sex). gf said her vagina is itchy/stingy after said sex (and bleed a little bit) with light pain during urination. is that concerning? ive had stds screened recently thrice using pcr?

Good you had protected vaginal sex; fingering is no risk for STD. And having sex in a bath or otherwise under water does not raise STD risk. No newly acquired STD can cause immediate symptoms, but your gf's symptoms might be caused by an infection that was present earlier. If the symptoms continue, she should see her doctor for evaluation, which probably will include STD testing. Good luck.