That episode SUCKED *** for being a season finale. Love that Carl is becoming more bad ass-ish. I think he explained it pretty well when asked why he shot that kid. And while I'm glad Andrea is gone, I'm kinda sad that there isn't anyone as annoying as her on the show anymore. So, the conficts (and writing) better improve next season.
And how cool would it have been if Zombie Milton actually helped Andrea for quick second? Ridiculous, I know, but it would have created this cool little, "Holy ****! He was right!" moment.