My breast seems to have a very pronounced diamond shaped areola after surgery. is this normal? (Photo)

The way the borders of the lift are tapped and dressed prevents you from seeing the areola and its shape. Your surgeon probably reinforced the surgical closure to help prevent spreading and to give it support. I'm sure well qualified plastic surgeons who are doing mastopexy/breast lifts would strive for a round nice shaped areola. With periareolar donut mastopexy, the outer ring of breast skin that is constricted down to the smaller areola will give some ruffling that might take a few months to smooth out all the way. Don't be worried and discuss all these with your surgeon the next visit.  

I doubt your areola is square after a mastopexy. I think you're confusing the border of the dressing with the border of the areola.

Please check with your plastic surgeon. He/she can best discuss and advise you. At one day post procedure there are many expected changes to come with swelling resolution, healing and settling. Good luck