Why was chipmunk in a lot of stress?

This sounds like the setup for a joke! To give you a funny answer, here are a few possibilities:

* He was late for his acorn-gathering appointment.

* He couldn't remember where he buried his winter stash.

* He was trying to find a good spot to bury his treasure, but every place was already taken by other chipmunks!

Let me know if you'd like more options, or if you have a specific story in mind!