Your game clearly reminds me of this one:
https://www.newgrounds.com/portal/view/605618
but that game is much better in many ways. The main problem is that the smaller fish you can eat at the very beginning are awfully scarce. It already tells the player that it will be too long than it should be thus not that enjoyable. And it even poses a risk that the game will disconnect from NG not awarding the final medals.
PS
After playing it for a while I managed to upgrade my shark to higher levels, so it is manageable. So far I can tell that the medal for eating another shark is not working. You should have tested all the medals by yourself before releasing the game.