Did we miss ovulation?

I was prescribed 7.5mg Letrozole and took them from CD5-9 and only started testing from CD11... but it seems like my LH has taken a nosedive!

I can't post a screenshot but here are my easy@home results:

CD11: 0.41

CD12: 0.24

CD13: 0.19

CD14: 0.14

CD15: 0.2

CD16: 0.16 (today)

I've never had a peak; can a real LH surge go from 0.10 one day to 1.10 the next? Do you think we missed ovulation? It just seemed so early to start having sex so soon after finishing the last tablet 🙃.

Edit to add: my CM was as dry as the sahara and I have really irregular wake-ups because I co-sleep with my toddler so I really neglect taking my BBT.