I had sex like the 31st of August and took plan b because of precum and then the 2nd of September we had a slip and I took it again. I got a light period mixed with brown discharge on the 6th,7th,8th and 9th. I don't think it was my period tho because it was lighter than usual(usually it is heavy) but it did bleed enough on the 7th and 8th to fill a slim tampon. I was suppose to get my period on the 14th and now it is 21st and I don't know what to do? Is this normal? Please help.