Why am I always tired?

Lately I've noticed I go to sleep almost straight away (normally I take a few hours) and wake up much later, and I have to actually get dragged out of bed, I'm still tired in the day and sometimes fall asleep when sitting down for a few minutes. Also I find I miss two or more meals often in a day because I simply don't feel like it. I feel anxious a lot too. I don't THINK I'm ill because I recently recovered from swine flu. My mum thinks I have anemia and I honestly don't know.. What do you think? Help please.