what's going on?

Please can I have some advice, researching on google is scary... we all know that, basically I've noticed that I sleep an awful lot recently and still feel tired sometimes for example last night I slept from midnight to 10:30am, is that too much sleep? I got up at 5:15am earlier that morning for work. I'm 20 and I'm also due my period but that's not usually a pls symptom, I don't think! I just feel like I've been sleeping in until 10:00 etc a lot recently when I haven't been working and still feel a bit tired when I wake up, which goes away with time and I'm getting worried:(