Really well done and cute entry! The sound ghost makes when getting hit is so cute. Graphics are minimal but it has an awesome aesthetic. I loved the parallax background. In game jams, they usually make pixel art disoriented and sometimes discordant, but you handled it perfectly! As a little detail I really liked randomized text in death scene, it's a little but good touch. I also liked the second mechanic, shooting. Heart targets spawn rarely, so it changes the way you play the game, you start to say "Pillar, next pillar, pillar, oh health, HEALTH!, HEALTH!" So RNG and spawn rate system handled perfectly :D
My only complaint and nitcpick would be sometimes cave pillars spawn each other so closely, that they don't behave so generously when giving you a reaction time.
Long story short, game is amazingly polished. Good job! Have a great day!