Its alright
I haven't played many shooters like this in a while, and the nostalgia was pleasant. I would like to recommend mixing things up, and maybe making it last longer.
Perhaps add different kinds of pumpkins. A boss or two would be nice, and maybe more than one stage. *cough* The Headless Horseman and Jack-O-Lantern are good ideas for pumpkin bosses. *cough*
For a quick Halloween game, it does exactly what it was intended to do. It helped get me into the Halloween spirit, if only momentarily. Keep up the good work, and happy Halloween!
-Geek