When is my ovulation? Help!!

Abigail

My fiancé and I are trying for a baby but I'm honestly just so confused. So I had the birth control that goes in your arm for 3 years and for that time I never had a period only spotting. I got that taken out about 3 months ago and haven't been on a birth control since. I've had a total of 3 periods ( the 6th of June , 28th of July and today the 16th of august). My <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> says my ovulation will begin right after my period ends, so that week after. Is that right? Ugh please help.