High fertility 2days after cycle

I started my period on the 16th of July and it ended on the 20 we just recently decided to try and get pregnant so I brought the clear blue advanced digital test to track my ovulation and the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> says My fertile days aren’t supposed to start until the 29 of July and I ovulate on the 3rd of August. I felt like I should start testing just in case the <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> was wrong and what do you know 2 days after my cycle I got a flashing smiley face I also got some pre seed to use as well. My question is is it possible to ovulate so soon after your cycle ?