Ovulation.

Alexandria
I am 23 years old getting married in less than two months. I've been tracking my period for a year and it's pretty much on point every month give or take a couple days at most. My period only last 3 days, two days are heavy to medium and the 3rd day it's basically gone a little discharge through the day. I've been trying to check to see when I'm ovulating by the trackers I have on my phone but when I test it says I'm not. I'm getting irritated I just want to make sure when we are trying to conceive in a couple months I know when I'm ovulating. Is having my period so short factoring when I should test to ovulate? Idk how many days after my period to ovulate  
Please help:(