There's potential...
I did like the feel of a barren forest in the middle of winter. I also enjoyed the detail you put into having the cool winter breeze around the character ruffle his hair. I felt that truly paid a bit of homage to the character's surroundings. I feel, however, you rushed the zombie animation a bit. I found it to be a bit disproportional. The pose involving the protagonist shooting the zombie in the head was a bit awkward, I would work on angles like that...or use a different one entirely if you don't feel confident. The spelling in your story is a bit distracting, there is also grammatical errors. If you don't feel confident in your writing abilities, I am sure there is are individuals willing to help you. The story could also use a bit more development. The single paragraph without building up the mood, on top of the spelling and grammatical errors, causes the reader to be a bit biased before the movie even starts. I won't criticize the length of the film, due to the fact it was a preview. I, however, believe there is much room for improvement.