Over the past week I have been getting tired so easily, headaches, and it's starting to affect my everyday life. I used to only have to sleep in until 8 as that's when I was so awake I would have to get up. But now, only a week later, I'm sleeping in until half ten until someone has to come up and tell me how much of a lazy person I am to sleep in until then. And by the end of the day I'm trying to resist the urge to go to be at four in the afternoon and sleep. It's the school holidays, but it's only been a week and this has never happened before. Could it also be my period was about a week late? I have only just got it, I don't know but I want to feel energised for the day, not tired and irritable. Can someone tell me how I can change this back?