I've let my dog lick my vagina before. (i tried pushing her away) i washed after.. can my dog or i get an infection?

Not recommended: Mucous membranes don't have a protective (tough) layer of skin over them (such as a hand). The genital tract qualifies as a mucous membrane because it's moist. As such, it's somewhat easier for germs to pass across from the outside world. You don't know what your dog might have licked before it came near you. You did the right thing which is to wash afterwards. Luckily, overall your risks are low