Information changes

Has anyonw noticed that the information changes or is it just me? I downloaded this app about 4 days and ago and after entering all of my info it said that I had a 33% chance of getting prego on 4/29 and that my next period is scheduled to come 5/14. Just 5 mins ago I look at the home screen and now it says that I had a 33% chance of getting prego on 5/1 and that my period is due 5/16. Has this happened to anyone else