How long after a positive OPK do you keep testing?

I had a very clearly opk at CD14 so stopped testing thinking I’d ovulate at CD15 for sure. Well my bbt only started to spike at CD18 indicating I may have ovulated on CD17 but since I stopped testing I have no idea which to go with. 🤷🏼‍♀️ Should I be testing with OPKs for some time after my positive? I knew there could be multiple surges during a cycle but I didn’t think there were multiple peaks too?

This is my first cycle using bbt charting and OPKs so there is a big learning curve!

Someone educate me?! (Ordered a fertility tracking book but it’s not here yet 😅).