Glow App??

Miss Me
So I downloaded this app so it could give me a more accurate detailed dates of when to conceive and when I am late. Now according to the app I was due to start the 7th. I also imput my last four cycles so I could get more accurate dates. So the 8th came around and I'm thinking Yay!!. I will see something says my percentage of pregnancy would increase. Although that was not the case, it decreased and pushed my date two days later. Now again the 10th and still no visit from flow. It has just pushed my days another two days??¿¿. So frustrated and it seems like it has completely defeated the whole purpose of me using this app. I could guess and not know what's going on by myself. I do really like the other features though like this room ♡ Thanks for letting me rant a lil.