Why is the only line i get on opk,not dark and only one day in my cycle????Please read?

I also used to get faint lines, and I'm on my second pregnancy, so I know that I was ovulating. You have a very quick surge, so make sure you test several times a day. I always got my best results at 10 am, and I never did charting either, I'm up way to much during the night. I once had a dark surge one morning, and by the evening I was totally negative. The fact that you have O pain and EWCM is good, sometimes it's a better indicator for me than the sticks.