Are you charting, too? I would go by when your rise in temperature was, and use that instead. Sometimes, your body is 'gearing up to O' and you will get a positive, then a negative, then a positive. Was the last positive darker?
IDK what to tell ya. I'm sorry. I have struggles with OPKs sometimes too. Most months though, I get a good progression from neg to pos back to neg. Hang in there.
Re: two positive opk on different days in same week?
My BFP Chart
My Ovulation Chart