What happened?

Kayla

This is my first month using OPK's but the last few days have really confused me. I know that a positive ovulation test will have a line that is as dark as or darker than the control line but my darker tests(taken on the 18th and 19th) aren't like that? And now all of the test I am taking are super light. Did I not ovulate or is this common? Please help! My predicted ovulation day is the 22nd.

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