Im cramping 😢

Hey girls! Last week I had a stomach aid for like the past 3 hours & it went away in that same day..& well me & my husband are TTC! This will be our first 🙏 we had sex in my fertility days & after I ovulated...in this glow app it says I was supposed to start my period like 3 days ago & some other app I have "period tracker says I'm supposed to start in the 19th (this Saturday)....can anyone answer my question? & please no mean comments, I'm very new to this. I got this app because I'm ttc & so I can chat with other woman like me ttc. Thank you!