Postpartum sex.

My partner and I had sex last night without a condom, it wasn't full blown but it was penetrative for a few minutes (like, less than 3 lol) until we stopped because oh my god, I am 4 months postpartum and had my first period end 3 days ago and now I am going to ovulate in 2 days time. I use Flo to track everything. Did we fuck up?! I am NOT ready for another baby, there is no room in our home for us as it is and we are so far off being able to sell and move elsewhere. 🤦‍♀️🤦‍♀️🤦‍♀️ I feel so fucking stupid.