Day 2 of positive OPK?

Erika

I took one yesterday at 3:30pm and got my positive!! We had sex right when I got it. I just took another one and it’s still positive. Is it normal to last for two days? Does that mean I’m supposed to ovulate 12-36 from today or from yesterday? I use the clear blue which only give a O or smiley face. (No blinking smiling faces)