... sunday after my period ended but i forgot and put it on monday instead. Then the second week came around and i placed it on my arm which got irritated so i had to take it off and replace it with a new one. That was a tuesday. It became my new patch day. Now i am on my no patch week, which i took off my patch. However because i didnt start on the sunday like i was instructed to, and my calendar has told me i should have started my period on monday this week, i have yet to start it. My patch is off for this week but since no period has came yet, will it come next week or this week? If it comes either week, do the periods shorten or will they last for a long time? I did a lot of research but nothing seems to answer my question