No it was a happier one. The section that seems closest is 79-87 of Guermantes in Moncrieff/Kilmartin, where he's at the hotel by Saint-Loup's barracks.; between "Mais, des le second jour, il me fallut aller coucher a l'hotel" and "Certains jours, j'etais agite par l'envie de revoir ma grand-mere ou par la peur qu'elle ne fut souffrante;..."; but this episode (nonepisode) doesn't seem quite right either, though I love it.

I wonder if my memory just sewed together the sleep bits of the Overture, the one you mention, the Guermantes one, and whichever others (there's a lot about sleeping after Albertine's gone I think), into some vague metonym for the whole novel.