the mysterious trash bag

i was sitting putting on my shoes. jarred was standing 7 feet away, a step into the hallway of our apartment building gently urging me to hurry up. having filled up our trash bag after dinner last night, jarred had taken it out of the trash can and tied it closed, and it was sitting by the door ready to be taken down the 5 flights to the big trash can outside. and then it happened. the whole bag suddenly convulsed back and forth for 2.5 seconds, like whatever was inside wanted out. and then as suddenly as it started, it stopped. with looks of horror on both of our faces, we just stood frozen for a second. and nothing else happened. so in an attempt to see if we were safe or if we should run for high ground, jarred kicked the bag. but it seemed that the boxes and trash inside just shifted around. so with a great show of manliness, jarred grabbed the bag and took it downstairs. a mouse? a rat? a cat? we will probably never know. and in fact, i hope we never know. but one thing i do know is that i will probably never take out the trash.