Oddly colored discharge

So today I noticed that I had a little yellow/green vaginal discharge. It alarmed me but everything else feels fine. I've been with my current boyfriend almost 2 years and I've never had this before.. I looked online and it said maybe gonorrhea but if it was that why would I just now be getting symptoms? Unless my bf cheated on me bc i haven't  been with anyone else. I just need some advice please.