I am using the purple cap test. On CD 10 I got a solid smiley face indicating peak fertility. However I hadn't gotten a flashing smiley face. So naturally I was confused. While I understand that you "must" stop testing after the solid smiley I thought maybe I had a faulty test so I waited for the smiley face to go away and retested yesterday and got low fertility. I tested again this morning and got another solid smiley. I ejected the stick and found that the test line is so dark that the control line was barely visible. Please advise.