Fishy vaginal odor when aroused?

I'm sure this has already been posted somewhere, but I didn't see a topic for it. I noticed that lately when I am aroused and masturbate, my fingers have a "fishy" smell afterword. I don't have any discharge or other symptoms, but this really grosses me out and I don't want to turn anyone off when I have sex. What could be the cause, and what can I do to get rid of the smell hygiene-wise? Thanks for your answers. (I'm a 19 year old college student and I'm gonna schedule a doctors appointment for it but I just wanted to see what you all would say advice-wise)