They shouldn't even have rats in the building anyway!!

Yikes! I just cringed over here just thinking about that happening to me. While I can't comment about anything related to your job, I think it's worth having a conversation with your manager to let him or her know about this. You shouldn't be in a position dealing with a panic attack while helping a patient nor is it likely a good sign that a clinic has a mouse problem. Hopefully your boss will understand. Keep us updated!