When Crowley hangs up on Dean there is an audible dial tone, despite cell phones not having dial tones.
Lisa is stabbed by the demon that has possessed her near the end. Dean continue's the exorcism and rescue's Lisa to the hospital. After Dean asks Cass to wipe Lisa and Ben's memory. They are lead to believe that they we're in a car accident. The wound Lisa has would clearly be a stab wound, not from a car accident.