Help with opk

Okay ladies, super new to opk so I'm a little confused with this one. Hopefully some help will given. Lol anyway the picture with three sets of tests were taken the 10th, 11th, and 12th. The single picture was taken this morning. I have been slacking with testing everyday, so this is all I have. And I'm confused. I thought you only ovulated about four days. I'm probably wrong though. Please help me, lol I also herd about women using opk tests as pt's. Very new to all this. Any advice helps!