The story was well developed. I liked the the opening scene in space because it looked cleaned- up and the good camera angle.
The audio was too loud in some parts, especially the beeping noise when he was trying to find his space ship.
It needs more audio in the last half.
I wish the alien was more detailed, especially since hes the focus of the story.
There also needs to be some more complex animation with the astronaut and alien, instead of just the two of them sliding across the scene.
Since you used nothing but photoshop as you said. Making an animated short with just that can be difficult if your new to it.
So I praise you on your hard work.
What was your teacher thinking? Using corel painter for an animation? I don't even think you can animate using Corel Painter. Never heard of anyone doing it.
Overall, I liked the story.