Changed dates in Glow. help!

So I was going back to add in past period dates and when I did it completely changed my fertile days and all that. My last period for December started on the 24th glow said my highest ovulation day was 1/4 and my clear blue ovulation kit gave me my peak that day as well. Well since I just updated its now saying my biggest chance of pregnancy is today. I did the ovulation kit and got a high fertility reading. I could swear that I did ovulate on or around the 4th. I had lots of watery cm (I don't really recall ever getting the stringy type of cm) I also have two children. Today my "updated ovulation date" I don't have much cm going on. Is glow wrong now? I am so confused