So confused

Allison • 26. Married for 4 years. 22mo 👦🏼. 1 angel baby 👶🏼. 🤰🏼🌈 due in Nov2018
Hi ladies! Soo here's the deal..I got a +opk on Monday and have felt sharp cramps since then. I went to the doctor this morning to have it checked out. She did a pelvic and discovered a follicle (or a possible cyst) on my right overy. She scheduled a sonogram for Tuesday and told me to go home and have sex just incase..but now I'm super confused. Is it possible to ovulate 72 hours after a +opk and also I'm on cd21 of 30. Since I ovulated late does that mean my period would be late? Sorry I know this is a lot..but any information or advice would be MORE THAN appreciated!