Okay, albeit i am awfully late, i had a quick look at this game of yours, here's what i changed:
fixed player's bounding box
fixed player's z-order
fixed timer and score (resets on restart)
made timer text more consistent
fixed the bullet behaviour
fixed the attack animations
fixed the controls (s key fires now)
fixed the monster pathfinding
fixed the monster attack
fixed the monster bounding box
made the monsters have infinite movement loops
tweaked the movement speeds
made projectiles be destroyed when off-screen
added damage to monster collisions with player
fixed the minimap
fixed the pause feature (you should have a "continue" button, however)
fixed the monster and player destruction sprites
tweaked the player and monster health
To be honest, then i just got tired of messing around with this stuff, so i guess the damage and health bars will be up to someone else to implement properly. How the hell does someone manage to screw things up so badly in such a simple project? IMO it's a mess that should be discontinued. >_>
Download (resaved as .caproj inside of .7z archive - roughly three times smaller filesize).
https://dl.dropboxusercontent.com/u/80437109/this%20game%20of%20yours.7z