idk what to do

i had unprotected sex jan 18 and took plan b. my period in jan was before we had sex and after taking plan b, i believe i had my period from jan 24-30. following my cycle i should have my period today or tomorrow. but i havent gotten it and i tested neg for pregnancy.

ive been having cramps for a day or two already and thats usually what comes before my period but i still havent had it today :/ could i be pregnant, should i test again, idk what to do please help