The problem was not that Albus could not think. The problem was that he found it virtually impossible to condense his focus down to one prevalent pattern of thought for more than a few seconds. It was near to harrowing, but with Draco's sudden arrival, he was at the very least presented with a pressing source of concern. Surely he'd be less likely to go mad if he had someone to talk to-- a reasoning, no doubt, that accounted for the penchant of the insane to talk to themselves. Charming.
Thankfully, when Draco spoke, it snatched at Albus's attention. For a moment, he'd been worried that he wouldn't be able to hear Draco at all over the buzzing in his mind.
"Mr. Malfoy," Albus recited, the only accessible reflex being one of formality. It took a moment more for him to realise that Draco's movement rang with purpose and intent-- and Albus tried very hard to prevent himself from attempting to suppose that it might be, for fear that the whole volume of possible answers would explode out of the back of his mind. Still sounding a bit out of breath, the words creaking slightly with the strain of keeping himself held properly together, he managed to say, "Have you lost something?"