Can you get pregnant if you touch your boyfriends penis but its dry then you wash your hands then finger yourself?

no It is soo very unlikley the only possible way is if he had some kind of "pre-cum" that somehow had sperm in it and then it didnt get washed off when you washed your hand (witch is very very very very unlikley) so pretty much my awnser is no.. there is probably less than a .1% chance of pregnancy in your case.