Hi Had Unprotected Sex On The 10-11 ( 10pm -12am)

Hi had unprotected sex on the 10-11 ( 10pm -12am) and I took plan B at 9 am on the 11th and now I've been experiencing yellow discharge and I'm kinda scared that I could be pregnant due to the fact it was 3 days away from me ovulating and 3 days prior to the 10 I had sex and at the beginning of sex the condom came of and it was in me but he said he didn't cum yet and we took it out and it looked empty. So could I be pregnant and does the pill cause yellow discharge