Visible crew/equipment: After Cam's really long drum moment, when it cuts to Gloria, Jay, and Manny entering their house, the reflections of the moving boom pole/mic and a crew member are visible on the window. (00:15:50)
Visible crew/equipment: When Manny gets done with the dentist Jay convinces him to go to the movies, and as they leave the office we can see the reflection of the boom pole/mic on the receptionist's glass window, at the top, left side of the screen. (00:01:40)
Visible crew/equipment: When Manny brings out an epee, equipment and a bald headed crew member are reflected on the polished guard's surface. It's pretty quick, but it's there. (00:09:45)
Answer: He has seen himself dancing, and is mortified at how bad he looks.