I’m four days late with absolutely no period symptoms. I’m definitely not pregnant. I have been stressing out for the last two weeks because I have a surgery coming up in a few days. Do you think the stress of the surgery has caused my period to be late. Any tips to help my period come? I’ve also had a change in sleeping schedule (going to sleep later and waking up later) as well as change in my day schedule (on vacation). I really don’t want to get my period tomorrow as it is the day of my surgery.