when does tww start?

Hannah • Hey 👋🏽 guys. 2 year old. Engaged. Trying for baby 👶🏽 number 2! 😍💙👶🏽😘🙌🏽
When does o the official two week wait start? Is it after I stop getting positive OPKS? Or the first time I got one? I'm pretty sure I'm in my TWW which is VERY exciting 
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