He'll probably notice the feedback loop Gabriel managed to get going to help with the Grace side of things. Fortunately, it doesn't require Gabriel to be paying attention or even conscious to keep running.

Gabriel stays unconscious longer this time although at least this time it was to aid in healing faster rather than just shutting down. When he wakes up again several hours later, he feels considerably better although still nowhere near a hundred percent. He estimates about another week after taking a moment to mentally check himself over.

Then he opens his eyes and frowns down at himself. It was time to do something about that shirt. What with the hole and being soaked through with dried blood, it has to go. One less reminder of what Lucifer did to stick around. It finally belatedly occurs to him to look around for Castiel.