I agree. There appeared to be set moments when he flicked or wiped at the outside of his eye without there being any tears being wiped away. He also stared straight down at the podium when he was seeming to gather himself. Then he launched from that emotional show right into vowing to take the action needed to stop future incidents, regardless of the politics. (Implied but unstated: crack down with more gun control.)
He also cried when he was reelected. Tears were shooting out both sides of his face. Axelrod must have had riot control police on hand with tear gas canisters at the ready when the magic moment came.