Confusion.

I took a 'nap' at 9:30 and it turns out I woke up at 6AM. So that's the reason for a  late post.
So this past week I've been getting very little sleep due to the lack of finishing homework earlier in the day. As a result I've been kinda of in a zombie like state at school for the past 3 days. So for tuesday and wednesday I got a total of about a little over 6 hours of sleep. That's less than what the average person should get in a day. So even with my lack of sleep somehow I still don't manage to finish all of my homework for all my classes. So as a result my grades are yet, still dropping.
So, a couple things that have happened to me because of my sleep deprivation. I woke up twice from 'naps' and had no memory of anything that happened before my nap. For example, I think it was last weekend I woke up at around 8AM and I remember the first thought in my head was, "How am I in my bed?". So I slowly get up and try to retrace my steps, but nothing comes up. It's a weird feeling losing a bit of your memory like that, it makes me kind of scared. So, I still don't know what happened that day and the same thing just kind of happened to me last night. I woke up to my alarm going off at 6AM and so I slowly drift out of my sleep and come back into reality. I check my phone and I notice that I received two phone calls, one that was 7mins long and the other one was 2 mins long. Now I have no idea what happened during those 9 minutes. If it wasn't for my phone I wouldn't have even known that I was on the phone last night.
Could this be a cause of not getting enough sleep? Slight memory loss? Maybe it's from exhaustion? I've heard from others that they're too tired to think, or people sort of mumble and rant on and on when they're tired. Either way, this is a bad habit of mine that needs to stop.
I keep telling myself after school to go home and finish my homework so that I could have worry-free time to do other activities, but that never is the case. I need more self discipline, this is my resolution.