Lots of things cause bumps in the vaginal area. There is no way we can know what caused hers. It could have been an infected hair follicle.
If it was a wart, you could have been infected, but please remember that it could have been anything, and there's no way for us to know what it is.
The scrotum has thick skin, and is not likely to be a portal for infection.
I wouldn't worry if I were you.