Which test is correct?

Hey ladies, so I've been tracking my ovulation for months and at first I bought the expensive ovulation tests, but that didn't last long bc they are expensive af! So I got these other cheaper ones and I love them, every month I get a positive, but never a positive pregnancy test. But this month, since I had extra expensive ones left, I decided to use one after I used the cheaper stick ones. I got a positive for both the cheaper ones, but looks like a negative for the first response ovulation test. Can someone help me out, which one is correct?