If i took planb within 72 hours but i only spotted for an hour & then a spot for a couple days. am i safe? i'm worried because it was barely anything

Can happen: If you are spotting occasionally following Plan B this can happen , however if you have skipped a period or have just this scant spotting instead of your period , please do a pregnancy test.

Plan b: Emergency contraception symptoms can include spotting or bleeding, changes in menstrual flow or your period may be late or early. That may not have been your period. Take a home pregnancy test & notify your GYN if your period is 7 or > days late.