Positive OPK this morning, negative this afternoon, is it possible I ovulated during the day?

I got a clear positive at 645am and a negative at 500pm same day on the same brand test. I expected it to still be positive. Is it possible I just have a short surge phase and potentially ovulated during the day?

I’m tracking BBT but won’t see that until tomorrow so was wondering if I should continue testing for 3 more days?

This mornings test

This afternoons

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