Perhaps it's a combination of his memories of his previous time in Mayfield rushing back now that he's returned to the town having a head-on collision with false memories the town is trying to implant, but the simultaneous dump into his brain leaves him so disoriented that for a moment he has trouble enough figuring out who he is, to say nothing of where and why and in what state. This beats any hangover he's ever had, and Antivan brandy has gifted him some extremely potent ones.
He finally half-climbs, half-staggers out of bed, holding his head and looking instinctively for Olivier - but there's no sign of her. He doesn't give this fact any immediate consideration, but instead heads for the bedroom door, ignoring the fact that he's not really dressed in the conventional sense of the word. Or at all.
He's passing a picture on the wall when he stops, shooting it a sharp look - and yes, that family isn't his. Well, technically, Olivier and his various 'children' hadn't been his, either(or so says one half of his still-swimming head), but this family isn't familiar. And after a few moments, Zevran realizes the house isn't familiar, either. He's been moved.
It's tough coming to these conclusions when half of his mind is insisting this is all perfectly normal, that he's always lived here, that he should go put some pants on before his son (???) sees him...it's like listening to two radio stations at once. But Zevran's assassin instincts, honed over a lifetime, give extra weight to the voice in his head insisting that something is wrong, just in case it happens to be true.
His feet make a beeline for the phone, even as he tries to stifle the voice that wants him to accept everything as perfectly fine; how can everything be normal when he's of two minds and they're both trying to shout down the other half? That argument seems to bring him some brief mental clarity - perhaps because there's no easy answer to that question - and when he picks up the handset and begins speaking into it, he merely sounds bewildered.] I am...quite confused. I don't believe this is the house I was once living in, and - I cannot imagine why I was moved. Or when. Have I been gone? Olivier, are you there? [Then, with a shadow of his usual humor - ] If you are, what terribly unlucky man awoke beside you? Does he live still?