Yes. Number of rats should be in top right corner. In first 2 levels it automatically transfers you to the next one - but in third, you need to go east (as text message suggest) and find... I won't spoil it :)
There's also text + invisible wall for few seconds, on hindsight, not best idea how to slow down player :D
I was also thinking to add something like "6th sense"/cat senses to point you in direction of next objective, but I didn't have the time to implement that. But I have it in backlog, maybe for real release.
Try again in story mode, you might like the end of game :D