Disorienting would be a somewhat stronger word than necessary to describe Clair's experience floating in the air. He was rarely this far up in the air, of course, his normal distance from the ground being approximately nil, perhaps a leg-length from his hooves if he was riding on Clarity's back. Technically off the ground but definitely less than a phone call away. From up here, if he was the worrying sort, he'd probably want to send a postcard with Wish You Were Here on the back, which the ground would be able to read about as well as he could, maybe a little better. But aside from looking down on ponies rather than up at them, he was also not quite sure which way was up. Clearly up is the direction his head is in from his body, so yes, he's still looking up to ponies, a bit farther from them than usual but still able to identify them as such with no problem. His point of orientation is whatever the brightest thing around is, which at the moment means his sister.
Until a brighter bean-shape with legs, head, and wings swoops up to him from the expanse of air beneath him, sounding for all the world like it was all ending and it's her fault, which she knows from her own personal experience of bringing about the apocalypse. Hard to argue with a track record like that, really. He waves at her and smiles, the breeze tilting him slightly on his string and setting his mane and tail streaming somewhat. "No, Brio, this isn't-"
"Oh, Brio! What have you done??" Clarity interrupts from above, sitting back on her haunches with her forehooves to her cheeks, pouring a generous helping of drama into her voice. "Woe is us, for such travesty has befallen us as to turn Clair's world topsy-turvy, with naught to anchor him to our glorious Equestria but the perilously thin string joining the two of us!" Clair sits(?) through the exclamation, looking incredibly at ease for having had reality shattered around him. "Tell us, dear Brio, what oh what have you done to bring this to pass? How did you do it? And what great trials must we overcome to restore him from this sorry fate???"
"...So how are you?" Clair asks, fully upside down again.