When in doubt, try it, but don't rely solely on it.
I have similar problems with turning it off without realizing it, the key for me is to set it just outside comfortable arms reach. It's close enough to hear it, but im required to get out of bed to touch it, which is enough to get me up and awake
I'm actually still using the same alarm clock I've had since childhood. It's super basic, but it's held up for more than 30 years and still gets the job done.
http://games.joshkirklin.com/sulium
A single player RPG featuring a branching, player driven storyline of meaningful choices and multiple endings alongside challenging active combat and intelligent AI.