Nice game!
I really liked the idea of more open to the player fishing mechanics.
I remember with horror the hours of fishing in Terraria, although it was fun.
Your game isn't particularly big for multiple scenes. Changing the fishing scene to and from the store was a bit laggy in terms of background music. You could have had a short animation and sound stop when you pressed the button, and then do the scene transitions already.
Or you could have everything in one scene, just off screen. Especially the player can quite often move between scenes. These are just my suggestions.
It would also be cool to see, instead of drag'n'drop cards with fish, how fish flounder, hanging on my cursor :D