It was yesterday that I went to Lidl. They did seem to have most items, to my surprise. The only things I was unable to buy were the flavoured Skyr yogurts but they did have the plain ones...
No Idea which Mercadona you went to but the Olula one was well stocked. They have put lines at the check outs, indicating how close to have your trolley to the one in front. There were very few shoppers in there. I suspect due to everyone being there on friday and especially, saturday, panic buying. It will e some time before I will get over the sight of the man taking 12 packs of loo rolls, each pack having 8 rolls in. He must have a very serious stomach problem....