Too hopeful??

So I had my normal period the 16th through 19th, and I obv BD on the 19th. On the 21st, I took 2 bc pills because I'm on the fence about having a due date around the same time as my first. But ultimately decided I just want to let fate decide. I then started withdraw bleeding on the 27th. I'm now on CD 18 if you count withdraw as CD 1. I usually O on 18/19 but I'm thinking I may have concieved somehow on the 19th. I feel pregnant, I'm craving things, have aversions, my boobs feel heavier, im super gassy which jsnt normal. Am I tricking myself or is it possible?