Fundamentals are good and I like that you change your attack based on whatever you killed last.
Not being able to block their attacks with a well timed melee attack makes the start really hard.
Also, I think you forgot to reset the kill counter on multiple plays. I would continue with the same amount of kills and just one enemy, but as soon as I killed that one, whole hordes would spawn :P
I'm sure it's a bug but it looked hilarious having 20+ enemies coming at me at once :P
Great job !