am i pregnant please help

so i had sex it was protected at first then it broke it was on april 30 my fertile day i took a plan b right after like we stopped he didn’t finish but he thought pre cum mixed with my cum so we took a plan b i was supposed to get my period yesterday but haven’t i took a pregnancy test and it came back negative right away but i have been feeling my stomach turn and have had diarrhea for a bit am i fine ? or am i pregnant?