I had 4 false positives on these tests I know 100% they were false and not a chemical because I got blood drawn and it was a 2. Not pregnant. But yet I took another test a few days later and got another line. Come to find out that I hadn't even ovulated yet. I have pcos and have very long cycles sometimes. I haven't bought these tests since.
Don't get frustrated! Try again in a couple days. I got my first positive on a store brand blue dye test. Confirmed it with a digital but I didn't get a positive FRER until 2-3 days later!