Possibility of being dehydrated?

I'm 13 and I've been been basically sleeping 14 hours a day and I my mom called my doctor and she told me I should drink more because she thinks I'm dehydrated. Do you think I could be dehydrated? I drink a carton of milk and a juice box at lunch everyday, like two cups of orange juice and another glass of whatever i feel like that day, and drinks here and there. My mouth isn't dry, I accidentally cut my hand and I had plenty of tears, and as gross as it is my pee is a normal color... so I'm really doubting my doctor's decision here since she didn't even make an appointment and evaluated me over the phone. This sleeping 14 hours a day is really affecting my life and I can't stay awake awake and one day my mom dragged me around town to keep me awake but I was so sick the next day she decided its better to let me sleep. So is being dehydrated a possibility?