Help me out

Hung out with the guy, I’m on birth control but this weeks I’ve been forgetful and doubling up. We didn’t have intercourse. He just fingered me. I don’t remember if he touched himself before he fingered me. I don’t think he did but idk. Idk if he had precum on his fingers before. I’m young and have had no sex Ed. I’m not ready for sex Ik. But I’m wondering if I need a plan b to be safe. Period suppose to start in 16 days roughly ?