Confused with OPKs and O date!?

Hi

I am just looking for some insight into what’s going on with my chart.

I had my peak opk on cd 14, assuming Ovulation on CD15. They then started to fade eventually becoming very negative. My bbt took a couple of days to rise but then since CD18 has consistently risen.

I have missed a couple of days on OPKs as was away with work which I know isn’t ideal.

However over the last 24 hours my OPKs have started to show darker test lines again. I am making sure that I test around the same time every day which is 10am and 5pm.

Any idea what is going on? Should I be worried?

Thanks xx

Any idea what is going on? Should I be worried?