When Danny is in the old woman's cellar, he reaches to turn on the light and it comes on just before he touches the pull chain.
When Steve takes out his phone and answers Max's call, his phone is upside down.
The killer tells his grandmother that she is "out of Heparin" when checking her pillbox and then tells her it is "the one for your heart". Heparin is administered by injection, intravenously or subcutaneously. The "pill form" is a drug called warfarin. Furthermore, while it can be used for heart surgery patients, it is not considered a "heart pill". It is an anticoagulant so he would tell his grandmother it is "the one for your blood".