TL;DR for the auction: south has shown a monster with 5+ diamonds, 4 hearts and all the controls. Your bidding is consistent with AKxxx Qxxx x xxx (or xx xx, or xxx x in the minors).
I was quite pleased with the auction here (mainly for having not gone off the rails for once), and 7♥ was cold barring a very unlikely first round ruff but after the dust had settled I wondered whether I should have corrected to 7N. It didn't even occur to me at the time with such a shapely hand, but I have at least one undisclosed trick in the Q♠, very likely another in the fifth heart. I'm now struggling to place partner with a hand where 7♥ is laydown and 7N isn't.
The scoring was IMPs, so the only question is whether I can prove that 7N is more likely to make than 7♥.
I thought I'd self-persuaded in writing this post, but changed my mind again. The hand I'm most worried about is - AKJx AKxxx AKxx, where partner's anticipating at worst three ruffs in the minors regardless of my distribution.