I’m confused, any advice?

Sooooo I’m trying to get pregnant and I’ve been checking my ovulation with the tests, so according to the app I’m not supposed to ovulate until tomorrow, however I took an ovulation test yesterday and the line was not fully solid but pretty dark, then today I take another one and it’s lighter then it was yesterday… I’m just confused now and wondering if anyone has any insight? I would think the line would be darkest today since I’m expected to ovulate tomorrow- my cycle is very regular.