Any ideas? Please help

So AF didn't come yesterday or today! I have absolutely no signs of her either. Last two days I've tested and all tests have came up with a vvvfl with color so I know it's not an indent or evap. Today with FMU I took another and my line isn't getting darker 😢💔 I'm getting scared I've never had any issues with other pregnancies or my daughters. By the third day should it being getting darker? The test this morning is even fainter then all the rest but with a bright light and right angle it's there 😔 any ideas?  Picture below is this morning test