Help!!!

So I got the Nexplanon inserted on 01/09, I gave birth on 11/15 and I haven’t had a period except the normal pp bleeding. I’m also exclusively breastfeeding my baby. So my SO and I had unprotected sex on 01/13 , he didn’t cum inside me but I’m still pretty worried that I might be pregnant since I had sex before the recommended 7 days. I also had a C-section so even if I wanted to pregnancy isn’t recommended. Please, I need advice!