Crazy BBT map... 😩

Abby

Ugh super confused over my BBT map this cycle... I thought it might have O’d on CD 18 since I got my positive OPK on CD 17

I work nightshift as an RN so my temps are taken at different times of the day but my last cycle I didn’t have any problems and definitely had an increase after I O’d. I’ll include pics of my last cycle in the comments

Any ideas or anyone have a similar BBT map??