No EWCM During Fertile Window

I had a lot of stretchy ewcm right after my period for about 2 days. I’m supposed to be in my fertile window now, but now my cm is white and creamy. I’ve also been having a backache and cramping/twinges for the last 4 days. Is it possible I ovulated early right after my period and got pregnant? My husband and I had unprotected sex on the last day of my period, and used the pull out method a few times after that. I have super irregular cycles and I took a test already and it was negative

I know these aren’t foolproof methods. We’re ready for a second baby but aren’t actively trying at the moment.