Oh wow, haha.
Alright so lets see. This is pretty good for a first (or a first good as you said) animation but there are of course a few bad points.
First I won't rate on the graphics since as you said they were premade sprites.
As for the animation it was smooth for the most part, though very slow, and a few things were less than perfect (like the flipping of guns that were, apparently, paper thin) and a few things just didn't make sense. (Such as someone dying by being shot in what would roughly be their thigh or leg.
And finally the music and sound effects were pretty good quality wise.
All in all it's good for a beginning but you have a lot of room to improve. It did make me laugh though when he jumped through the air for no reason to smack into walls. Good work and I hope my comments can help you improve in some way.