Any BBT experts out there! Need your opinion!

Hello everyone! So I am due for my period this Sunday and I have a pretty regular 28 day cycle. I have been trying for baby number 2 since May. This month I decided to temp and I tried my best to take it at the same time everyday. According to ovia, I ovulated on day 17. Would you guys agree? However another app I have says I ovulated on day 19. What do you guys think? I had sex on day 12, 14 and 15 on my cycle and so far my temps have remained elevated since ovulation. Do you think there is a good chance I’m pregnant?? I think I’m going to wait to test until Sunday or Monday!