That may be normal for you. My daughter needs a lot of sleep. She sleeps hard and doesn’t hear her alarm sometimes. She is the only kid I know who came home from high school and took a nap. I would be interested to know what you learn about this.
I went out last night with a few of my civilian friends, and two of the three said that without an alarm, they will normally sleep 12+ hours. So is probably is somewhat natural for me! As long as I have an alarm, I'm OK. Since I joined the military, I've gotten used to sleeping just 5-6 hours a night, and sometimes less (as a civilian, I would usually get at least 7 hours a night). It was easy to get away with minimal sleep during Basic Training, since you were moving around and doing stuff all the time, sluggishness would get you yelled out, put in the front leaning rest, etc.
Although, I had a generally intellectual AIT, so you got sleepier a lot more. Some people would take caffeine pills and the like. I strongly resisted energy drinks until the very end (Full Throttle was my specialty). But I quit it on the very last day of school, and won't touch it again unless I have to (I mean, really have to). If you sit down in front of a computer dispassionately for many, many hours, the sleep monster will get you. Guaranteed. Especially when concentrating on what you're doing is counterproductive (i.e., copying Morse Code)...