be cacking it

slang To be very nervous, anxious, or fearful. A euphemistic variant of the more common (and more vulgar) expression "be shitting it." It was my first performance in front of a live audience, so I was cacking it all day long beforehand. The boss said he wants to talk to me in private later on today, and now I'm cacking it that I'm going to get fired! Yikes, what did you say to those students? They're totally cacking it in there, thinking they're going to get expelled.