When a player gets up and walks off the field to the sidelines or walks into the locker room, you always hear the announcers sigh with relief and say "well, THAT'S a good sign. He's walking off on his own accord". Just because a player is walking off on his own does NOT mean that he's "fine". I've seen too many times where a player walks off... and then you find out he's got a torn ACL, MCL, etc. and is out for the season. I usually take reports like that with a grain of salt until the player has been examined and an official report is made.