Is glow app good to monitor ovulation days?

Lulu

Hey guys,

I have been using <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> to monitor my ovulation, so i will avoid having sex with my hubby, unfortunately during our holiday i couldn’t keep track and ended up having sex on my ovulation days, when the app stated i am 35% risk of pregnancy.

Then my period was 4 days late, then i got scared thinking i was pregnant, so I took two pregnancy test from clearblue came back negative.

My question is is glow ovulation days wrong?