Demario Davis after his interception

Watching live, I felt he gave himself up.

Watching the replay, he definitely slipped and right after getting up probably assumed that they ruled that he gave himself up but if I had to guess, he never heard a whistle blown so he tried to return it since he knew he was never downed.

Don't think a whistle was blown because the official on the LOS on the Saints sideline at the bottom of the screen continued to run with Demario as he returned it. If a whistle was clearly blown when he went down, the official wouldn't have ran with him.