BBT expertise?

Brooke

This is my first time charting bbt and I was hoping someone could shed some light on what is happening on my chart. I’m 5 days away from AF and this morning had a HUGE drop in temp. I’ll obviously take my temp again tomorrow morning and hope it goes back up again, but really hoping this big drop isn’t an indication that I’m out this month (3rd month trying after MC). Any help would be muchly appreciated x