STDs are not simply infections that happen to involve the genitals. They are sexually transmitted because they require far more than brief casual contact for transmission. There is little or no risk for the sorts of events you describe, with no transmission by fingering. If that resulted in contaminated genital fluids on your hands, there still would be no possibility of transmission to your own genital area, or anywhere else, such as mouth, skin, eyes, etc.

So no risk at all and no need for testing after such an event.

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

HHH, MD