He felt it even before he heard it, his sense of hearing as distorted as most of the rest while he lay there. The healing spell tingled on his upper arm, permeating the wounds and closing them up with a fluttering sort of softness. If Severus wasn't so groggy, he might actually enjoy the sensation. It wasn't what he expected; until the larger wound was tackled, sending such a searing pain through his arm and racking his body that he managed to tremble. Squeezing his eyes tightly against the sensation, his throat forced out a pained gasp and a wrenching groan to follow. He tried to curl in on himself, but the most he was able to manage was rolling his head and drawing his right hand up, latching onto Lily's robe against his head and balling into it.
His hearing was starting to come back to a point where he thought he heard talking. His pain addled, yet contrarily numbed brain still wasn't sure who it was that had come to his rescue. All he knew at the moment was the warmth sapping from his body and causing more violent trembles that brought even more pain until he was constantly sucking in his breath to fight it off.