Did Stacey tell Bradley that she killed Archie?

And thats why Bradley told Stacey to run, when he was on the roof, so she would get away. Thats why stacey kept saying it was her fault, and when she said she was lying to Bradley when they were up in the room. She said she wanted no more lies, eventhough she was talking about the babys father, she could have been talking about killing Archie as well.