Calling in sick; you might want to check your cell phone

So today a coworker called in sick several hours before his shift was to begin (my coworkers usually report to me on the weekend). He sounded sick but due to his track record, I had doubts. Funny thing is, he accidentally called me right after making his first phone call, only he didn't know it. His several minute long voice mail was complete with the sounds of his laughing and talking. He sounded happy and hyper, not like the incredibly ill sounding person who had just left a message. I could hear a lot of noise in the background, similar to what you'd hear in a restaurant, bar or other public setting

Not bright.