I touched a woman's vagina, on the outside, briefly, for like a second or two and a few minutes later I had a hair on my tongue and I picked it up with the same hand. I did not have any vaginal fluid on my hand nor she was wet and I did not put my finger inside her vagina. What are the chances of getting any std? 

Thank you!

There is no chance of any STD from such a superficial exposure. That includes HIV. Nobody ever gets STDs by fingering or other hand-genital contact. You are not at risk even if this partner has every STD you can think of!  You do not need testing and can safely continue unprotected sex with your regular partner, if you have one.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD