Temps not matching opk?

So I know you need 3 rising temps that are higher than ones before. Its seems like my temps were starting to lean towards O on CD22 but didnt. And now my temps are rising but they're not higher than the days before... So why dont my temps match my opks. I got a very positive on CD 26 (pic below) and very negatives days before. Could it just be my thermometer? I use a regular one but it's usually worked for me. Should I just discard the temps on CD 23/24 or just leave it.