I’ve been working on dream recall (just started LD a few days ago) and I’ve set an alarm to wake me up after 6 hours. I want to write down my dreams when I wake up but the problem is I can never remember waking up. I’m not a very heavy sleeper. On the few occasions when I do I just go right bak to sleep. Any way to help? 
Set two alarms. That’s what I have to do to wake up in the morning at all.
Either that, or make the alarm a very scary tone that is also VERY loud.
Why did you set the alarm to wake you up after 6 hours? It’s perhaps too early for you, that’s the reason why you go back to sleep.
I agree with Basilus West its too little sleep. If thats not the case just put the alarm clock on the other side of the room so you have to get up. Annoying i know but it does the job