Chances I could be pregnant?

I recently switched birth controls and insurance wouldn't cover it so it was going to be $160 so they were calling the pharmacy to see if there was a generic brand. My birth control only has 4 brown pills (period pills). I took the last pill I had on Saturday (a period pill so yes technically it would've been the last pill on my period but it went on through most of Sunday too) morning but didn't have one to take Sunday as I was out. I had sex at 1am Sunday morning. I got my prescription on Tuesday morning and took a birth control pill. I also ended up taking a planb morning after pill Tuesday afternoon as it said you could take it up to 72 hours and 72 hours would have been 1am Wednesday morning. I'm just really freaking out and have felt terrible and just wanted to know what the odds were of being pregnant.