The Ant amount will be increased after you won the challenge. And another increase after you beat challenge 2.
I really like the game not to be easy mode and that you need to try and fail in order to learn new tactics.
From what i see on your post, you have too many workers. 12/13 shall be enough for the first challenge, the rest you build soldiers. Give your workers NO job, let them be free so that they frequently bring eggs to the breeding tiles in order to replace the dead soldiers quickly. Before starting the challenge, make sure that you have decend food on storage for re-breeding. If you think the first is challenging, wait for the second formacarium challenge^^
It is all about the resources.
And sorry for my English, i am not a native speaker.