There is potential here. I like the idea of this game. Here are a couple of notes if you decide to continue with this project:
1) if you want to make it an endless game where enemies continue to arrive, then maybe every time the player reaches a goal, different types of enemies appear. For example, you start with regular ants, then termites, then fire ants, etc.
2) Definitely add music and sound effects.
Otherwise, this was a good effort.