Stupid stupid stupid. Why did I do that?!

Okay so maybe tmi but I ended up having sex for the first time at 4 weeks postpartum. It was real quick obviously since it's been awhile. When he was done something just clicked in my brain omg I'm not pregnant anymore and am not protected from pregnancy! We both started freaking out pretty much kicking ourselves in the ass because honestly, how in the hell did that slip out mind? I guess we were just used to not having to worry about it. 6 week check up is the 18th. PRAYING I'm not pregnant. I already have two kids I don't need anymore. I cant believe we were so stupid...