This game was so much fun! It was pretty hard at first, but was able to beat it after a few tries.
The health bars and level bars are not really intuitive. I didn't realize the red bar was your health, and when ships attack the mom, they're attacking you too, as well as them hitting you directly, or staying under water for too long. Maybe explain what the bars are in the tutorial too?
All in all it was really well made and visually nice too, with a lot of room for expansion, maybe make the next level where there are more and bigger ships, but the baby kraken gets more powerful?