Plan B pill

Had unprotected sex, (for a continuous amount of time) so I took a plan b pill the following Monday morning on the 30th of July. I had my period the previous Monday in the 23rd of July. I always have regular periods. Once or twice a year is it late. I just had what I can only assume was my period again this past Sunday August 5th. Too early, which I can assume is due to the contraceptive pill. Anyone think my period will pick up again around the 20's? Or again at the beginning of next month?