yea, now im thinking i might have caught something from my gf.
Does she have genital or oral herpes?
If she has genital herpes, you can't get it that way. Oral herpes can be transmitted that way, but you'd have oral symptoms, not genital symptoms, and you are far more likely to get colds, flus, strep, etc., from sharing pipes, etc.
You do need to get the burning checked, as that could be an std, but it won't be from this encounter.
stds of the mouth wouldnt show symptoms in the penis if thats what your speaking of . and i dont believe herpes would b transmitted that way.