Should i take plan b?

I know this is dumb but need some reassurance. I am 6 weeks post csection. I havent been cleared for penetration yet but my husband and I got caught up in the moment and rubbed against eachother for a bit. There was no penetration but probably precum. I know women tend to be more fertile right after pregnancy. I am exclusively pumping breastmilk and havent yet had a period. I am scheduled to get my birth control implant in 2 weeks. Help.