So after my period I started taking the ovulating kits. My fertility window was supposed to start Saturday and end next Thursday and the "ovulating date" was the 13th.  So yesterday the kit showed high fertility so I was updating my log to show I had sex and then I saw I could make note that I took the test today and that it was high then I noticed my "fertility window changed. I never even thought it would change and now that it did, I can't really solely go by just the app dates.