how many days a week are you training and for how long? honestly, if you're hardcore training, you're not really getting enough sleep. If you sleep from 11pm - 5am, that's only 6 hrs bro.
You say you could sleep 11-13 hours on any given day, but have you actually slept that long?
There could be lots of reasons why you're so tired. How much water do you drink? Are you on any medication, either OTC or Rx? How many calories are you eating every day? Do you have an inordinate amount of stress in your life? Are you depressed? Anxious? Are you taking stimulants?
Some people just need more sleep than others.