Chance of pregnancy & discharge

ok so this is my first cycle after no longer being on birth control (mirena) so I am not to sure of my cycles. I am also unsure of what discharge is which. But we are not trying for a baby and have been withdrawing (I know not it isn't 100% effective. If we get pregnant then it was our time to have another blessing) but last night I had clear stretchy discharge and it was a decent amount... as if I was arosed which I wasn't and today we had sex and he didn't withdrawal so what's the chance of pregnancy?