its good as beta, id say make the stick figures more like yourself minus the zombieness, and make the arms longer so that they dont seem as if they are chopped off.
I think this is a very good idea and you should continue with it, but still polish it up a bit :)
Im going to be honest and say that, if this is your first attempt at a game, its better than most first attempts.
Now, the things you could improve on are:
1. Better graphics, maybe invest in a pen tablet to draw on.
2. Less linearity, make the gameplay differentiate, not just you standing with a gun shooting floating stick figures next to a wall, maybe shooting stick figures behind a steel wall
3. Make some objective, because shooting random things to no avail is not fun whatsoever. Maybe have him progressing towards some goal, maybe walking towards his house in stages.
Overall, it was ok, but it definitely needs improving, this is an ok beta or a test for honing your skill.