Clear blue digital opk

Katrina
So I want to know how well did these test work for you?? So I'm in "fertile week" and I decided yesterday I'll pick them up and try and see how it goes (they have been sold out in stores around me for some reason) so  when i took the first one it showed the smiley (peak) and I still had 3 fertile days left...  Well last night I had strong cramps on the left side this am I had strong cramps on the right. (I've seen ppl have ovulated from both ovaries and that's just doubling my chances I hope) have I ovulated??? I dipped another stick this am when I woke up and it was way darker than the first one... Are these test to good to be true??? Has anyone gotten a bfp using them??? Does anyone have any advice???