Worried: HELP ME!

Chasidy • live life like no one is judging💋
So ever since I had my lil girl, I've always been a little late. But before I had her, I started every month on the same date. Well, I was suppose to start on the 23 or 24 & still nothing. I went to my obgyn yesterday & I'm negative for pregnancy. Could it maybe stress related on why I'm late?