Can sitting on the couch for too long actually hurt?

I've been lazy for the last couple of days. Who am I kidding.. weeks. I haven't done much in terms of exercise and have been comfortable enough sitting on the couch, eating pizza, watching tv and playing xbox. But i'm starting to notice a little strain in my back and an unsettling rigidness in my neck. Whenever i lean forward to get close to the tv (usually when i'm engrossed in a battle of epic proportions on the grid iron of Madden 2004) i get this strange sensation of pain searing through my back all the way up to my neck. It's as though my body is screaming at me to get off my ass and do something with my life.
My couch is comfortable, I'll tell you that. But is it TOO comfortable?
Has it become so comfortable that the effect has done a complete 180 and is now the exact opposite? To be honest, i'm loving my slob lifestyle, and i find it quite annoying that excess comfort is becoming a painful detterant to sitting around all day doing nothing.
It's quite ironic in fact, and i'm hating it.