Grand rising 💛

This weekend was my first attempt at using opk. The tracking app I normally use predicted the wrong O day. Which is when I first tested on Saturday. I happened to check this app and noticed the prediction for O is tomorrow so I tested again this morning after being discouraged and BOOM the line got darker. I have been reading that after it’s positive it takes 12-24-36 hrs to happen. Is this accurate? Am I ovulating? Also, my SO and I schedules clash until Wednesday. We literally have an 1hr together this afternoon and 1hr tomorrow afternoon to BD. Will I miss the O period ? Helpp