Nice one, I liked the added replayability built in by giving me two choices of weapons at the beginning. Highlights were the pixel art and overall game feel - screen shakes, particle effects, the good stuff that give a little extra polish. I'm not sure if you had health pick ups at some point that I might've missed, but that would have been appreciated - maybe a choice between refilling some hearts or powering up a weapon at the end of a level. And yes, always nice to give players a second or two after they enter the room before opening fire on them!
But you can be proud of this one, especially since you made everything during the jam. It's a really well put together game and I had a fun time with it :D