I'll assume you're smart enough to know that if you didn't want it reviewed it shouldn't be on Newgrounds. With so many other sites where you could upload it for fun (or even in the dumping grounds) the only reason you would upload it to the main site would be so that many many strangers can see it (which obviously means they're going to comment on it).
You asked us to take it easy in your author's comments, so I will, but taking it easy doesn't mean pretending it's better than it is, just that I won't ask you to go die or anything. Your art was decent, but this flash has a large number of areas you really need to improve on.
1. There is no preloader. You should learn how to implement a preloader so that your flash doesn't start before it's loaded. This very site offers free, ready-to-go preloaders.
2. This flash loops endlessly. You should really have it stop at the end with a replay button so that the viewer has the option of watching it again or not. Alternatively you could use one of the preloaders I already suggested which would prevent the flash from endlessly playing.
3. This flash is too short. Flashes like this are usually good for practice, to make sure you understand the basics, however that does NOT mean you need to put it on display. Before you upload a 2 second flash to the site you need to ask yourself if it will be entertaining to people other than you and your friends. It's really exciting to realize that you've animated a face turning, but you have to understand that the people viewing and voting on these flashes have already seen it, several times, so the joy of knowing you made something just isn't enough to warrant a good score. You'll be graded on the quality of your flash instead, which brings me to my next point.
4. There is no plot. This makes pretty much no sense. There's not enough time for it to, really. Your flash should tell a good story or at the very least a good joke, this has an angry guy scream a rather random line and then Teemo appears. Does what the guy says have anything to do with Teemo? No, I really don't think it does. So it's just some random stuff. It makes no sense with no significant punchline, so I'm not entertained. Since the bulk of a flash score is how entertaining the story/joke it's telling is (or how fun it is to interact with if it's a game or something) then I can't logically give you a score on par with a ten minute flash when all you have is a 2 second inside joke with minimal animation. Doesn't matter if it's your first flash or your 500th, you'll still get a score based on what the quality of the flash deserves.
Overall, I hope this helps you improve and I hope that in the future you try to get your flashes to at least the 20 second mark with some real effort behind them before you submit them to the Newgrounds flash portal.