Here's my first time using brush.
http://filz.us/G4f

Nice One.

Looks good, you should work on not resizing so much.

Resizing, and the last hit was unclear. Smooth though, keep practicing.

hmm, resizing. and the kick was not really good

make these corrections;
1.make the size of the head similar (the size of left one is way bigger than the right one)
2.add a bit more frames to the final kicks part so that the reason for the fall seems more clear
otherwise ur effort looks great!keep up the good work dude XD

Resizing
Avoid doing stuffs like this, it will make your animation completely not entertaining (not really). Use guidelines so you'll know how tall your stick should be.

Kick animations
Did the black stick kicked the blue one? I can't answer it since it's not really clear. Practice animating kick animations so you'll know how to animate a kicking attack.

Everything else is good and your animation was smooth! Good job!

The first punch makes no sense at all, he like, superman punched him with no momentum.WTF.
And the second punch could use alot more force, he probably should have hopped in the air a bit too.
The last kick was unclear as fek and the whole animation was choppy and wobbly overall.You should try to add more inbetween frames and
work on your anticipation.Also the reactions for the black sticks hits are bad.Its really choppy and when he falls to the ground, its like paper, he could come back up because of
the impact with the floor/ground.That kinetic energy...

Thankyou guys!

Looks pretty good! However, I have a few issues to address.

The reactions from the stick on the left's attacks don't correspond to the actual attacks. Like for instance, if the stick was punched in the head, I'd expect its head to move swiftly in the opposite direction of the punch, while the rest of the body shouldn't receive as much attention as the head.

Also, for the second attack, it seems as if the stick on the right is walking straight towards the stick on the left as if it wants to get hurt again. It shows no sign of retaliation whatsoever. Try to at least bring its arms up into more of a fighting position so he can show he has at least a chance up against this guy.

Also, the animation itself was a bit choppy and it didn't look all that fluid. Your movements are still readable but it looks seriously unnatural because of the choppiness of the entire animation. Try to single-frame more if you're double-framing or just boost up the speed of your stick's movements. It'll look good, I promise. :)

Anyway, nice job! I hope to see even more improvement from you. :D

Well, to my taste, the head was a bit to large. If it is your style, keep it going. ;D