So confused

It is 2 days after AF ended and i do t know why but I decided to do an opk. I'm not supposed to be in my fertile window until the 23rd. This is what showed up on the test.  Did I miss my fertile window? I'm so confused as to how it happened it so quickly after AF. My cycle lasts 5 days. Two heavy days then two light and last day is spotting. Anybody else have this happen or any thoughts? Thanks in advance for any insight you can give.