I read up on it a lil genetic. Maybe you can help me understand. So it says that it happens regardless of stimuli, so if you should behave accordingly to what you personal experience. Say there is a change in routine, do you think you would become more irritated because of the extra stimuli? Example, a annoying person spent the night and I was extremely irritable in the morning. Or say I am doing something and am interrupted in my "calm time of day", and I get annoyed or irritated, would that still consist of this daily internal regime?

It is consistent it says and I can say I have always been more of a morning person, so this does sound a little like me