I was reading that in the comics the phone call is really Rick "hallucinating" as a way to deal with Lori's death. Psizzle got me on the facebook page for TWD and everyone was speculating if Lori was still alive but then said the director confirmed it on the Talking Dead last night that she was really dead. IDK...I'm still stuck with the whole where are the bones thing too...maybe that's part of the mystery! They were also saying it was Carol's knife that Rick found where Lori's body was supposed to be??
It's the knife Maggie used to cut her open she dropped it. And your right in the comic Rick did find a phone that was "ringing" and it was Lori on the other end and he talked with her for a while because he was nuts. It's part of his transition as a guy who doesn't want to lead to a guy with nothing to lose and a badass. My biggest issue is the phone didn't come into play until more than two months after they were gone from the prison. If they are gonna jam this much I to a season. This show only has one left cause Kirkma does not have much left to write for the comics IMO