This comic feels like it just falls short of making sense, but falls short in every possible way. The fact that you are old is not "scary" even if that is sometimes the word people use; no one sits up in bed at night because they are suddenly older than they realized. Also, 8 year olds obviously don't talk like that.
I note that this is at least our third reference to 9/11 in the comic, not counting some throwaway lines, and I'm not sure that's a good thing. Obviously I am not going to say he shouldn't talk about 9/11, but using it as a default "traumatic event" starts to feel like latent Cyanide & Happiness-ism.
It's also not even the first time he's done these "oh shit i'm OLD" comics; see comic 354 or 447 [update: Or, as Daniel points out in the comments, 218] for others. Also in some ways comic 493 seems to be getting at this same idea. Yes, people get older. Yes, sometimes it can be jarring. Everyone knows this. This happens at every anniversary (the 2008 election was almost a year ago???) and it's an old boring idea.
Also, way to skip out on some cool lighting effects with the flashlight, as it is it looks like he's just about to cut a hole in his head when he turns on the lightsaber he is holding, or something.