Overall: Very good for a beginner
Art:
Decent in some places, poor in others. You did well with picking out the colors and incorporating cutouts (I like what you did with the police badge). Unfortunately your overall drawing skill needs work (look into shading). Perhaps next time you draw stick figures you should use the line-tool for the limbs and body. I say this because the gray lines making up your figures give them a segmented look and the lines on the arms are messy.
Animation:
There was little actual animation and a heavy reliance on tweens (which the expert critics usually whine about). I guess tweens are acceptable for a scrolling background or a car going in a straight line but frame-by-fame is best for say blinking eyes or a tear drop rolling down the face. The fire on the rocket should have been moving. I'd suggest at least a two-frame animation involving two slightly different drawings of the flame. My main complaint is with the rain. Not only was it poorly integrated but it froze and started a new copy when it started over.
Audio:
The sad music did very well to set the mood for this but there was no sound effects.
Misc:
The concept of this was beautiful. Making an animation to regain a lost friend (even if it's an e-friend) is a noble cause. However this was greatly diminished by the tea-bagging bit at the end (which should have brought the rating up to "T").
You should also look into preloaders and stop buttons.
Overall:
Work on your drawing and animating skills but also spend more time on your work.