please help!

This might be silly, but i love hearing opinions. I have a 25 day cycle and I am currently 8 days past ovulation meaning I'm in my TTW. I haven't had to many pregnancy symptoms just sore nipples, bloating, and decreased appetite. I don't want to take a pregnancy test until the day of AF because I don't want to get a BFN. I have been ttc for over 2 years with no success, but this cycle I did three things differently...one: I used OPKs to track my ovulation, Two: I used preseed for the first time during ovulation, and three: I tried the pineapple trick 🍍. This morning I decided to try an opk instead of a pregnancy test because I read they can detect pregnancy too. What I got was an unusually dark line. It's it does seem a little lighter than the co trip line, but typically when I'm not ovulating my OPKs are very light in color. 
What do you lady's think? Has anyone ever used OPKs for this reason, if so what happened?