plan b pink period?

so i took plan b exactly two weeks ago and i’m supposed to have my period begin tomorrow, i was on the toilet and noticed kind of a thick pink blob like come out of my and i wipes and it was a pretty decent amount of thick dark pink discharge, is this my period and is it caused my a side effect of the plan b? i put a pad on and nothing is really coming out - i am having like kinda bad cramping though, is this normal? just the beginning period blood trying to get thru all the hormones that were released from the pill? please help!