What is my actual due date?

Ch

Sooo July 9th was the first day of my last period. Putting me due on. April 15th BUT the scan I recently had measured me at 18.2 weeks so I’m trying to figure out my actual due date. Ultrasound tech put me at May 2nd but i have a hunch it’s more like the last week of April. Did I just ovulate late?! A friend mentioned this and maybe that’s what happened 🤨 Help anyone good at math?! Lol