Wish you guys would watch the video about stingers that I posted . They can linger for several days.
We're all aware of what stingers are ... it's very rare that they last for long ... especially several days. Sometimes there's some lingering weakness, but it's not enough to keep you out of a football game.
It's possible this was a stinger, but that's low on the possibility list.
Here's what I noticed ... he had a different equipment setup this game ... he usually wears no sleeves, and then has a compression sleeve on his left arm that goes up to his lower/mid-bicep. This time he had loose white short sleeves, and a different blue compression sleeve going all the way up his arm, disappearing into the short sleeve. Possibility something was bothering him before the game started and they had it covered/taped up.
The issue first appears to have happened in the 3rd down in the 1st drive of the 2nd quarter (BSU drive carried over from the 1Q) ... he rushes in and kind of falls forward, engaged with the OT and lands on his left shoulder, the tackle follows him and as Carter is rolling, the OT jumps on him again and rolls with him. Either of those (the hard impact to the ground or the impact from the OT as he was rolling) could have caused the issue.
The next drive, the first 2 plays, Carter isn't out there ... the 3rd play, he's out there as the DE and on the snap, you see he has the left arm held like it would be if it was in a sling, and he weakly trots after the play, which is to the other side, and without any contact, and still holding the arm like it's in a sling, he motions toward the sideline to bring someone in and he leaves. You usually wouldn't hold your arm like that if it was a nerve weakness issue, like a stinger. That's more indicative of a dislocation or a muscle issue.
He's later shown on the exercise bike, using both arms to move the bike's arms.
The next time we see him is later in the 2nd quarter, with a trainer attending to him. Camera angle sucks, but you can see there's now a white wrap over the blue compression sleeve ... it's wrapped over the top of his bicep, and then it's also wrapped at an angle going up toward his shoulder ... and she's trying to actually cut part of the compression sleeve away, in between the two wrappings, and he's in obvious discomfort.
My guess would be either that dislocation that they tried to harness up so he could give it a go, or some upper arm/shoulder musculature issue. You wouldn't handle a stinger like that. Given how the injury appeared to happen, I'd lean toward the shoulder dislocation (falling into the ground shoulder first, while going forward, and then the subsequent OT driving into him and into the ground as he rolled.