My <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> app shows my period is due the 13th but Glow shows the 20th and according to my LMP 8/17 or actually the date I started bleeding after my chemical pregnancy being a 28 day cycle it should be the 13th so it's throwing me off as far as when I can test, which one I should go by. I'm confused. I charted ovulation and reached my peak...had cramping and sore breasts a little nausea but now breast soreness lessening and I took home pregnancy test yesterday x2 and both negative. I'm confused and just want to know how to use this app because I want my rainbow with the love of my life! I'm 42 (have two sons 25 & 16- BF has 16 yr old son) so it was a blessing being pregnant last month and we weren't even trying but it ended in chemical and now I'm doing everything right it's so frustrating!