Feel like i am losing my mind.. lines on some tests yet not others??

I feel like im losing my mind. I got a faint line on a onestep strip pregnancy test off of ebay (will post picture of that also). The rest of that day i kept getting faint lines. However i dont really seem to see anymore on them now?? I did a superdrug own brand test yesterday and BFN. Did another one this morning and got a faint line (will post pics of that) I took it out of the case and took picture straight away. I got a BFN on this mornings onestep one. Im so confused. Advice?.