Fertile Window Troubles

So, according to Glow, my fertile window was supposed to start Monday, April

27. I started taking ovulation tests on Monday. It is now Sunday and I have tested as low fertility every single day using 2 brands of tests. Last month, I tested High for 5 days and Peak for 1. Should I be concerned or just wait and see if it's going to just be a really long cycle? I have never had a cycle this long but it's going to be at least 35 days. Help!