Some advice please! Clear blue digital - pregnant 1-2 now says not pregnant

Ok so on Tuesday morning I took a clear blue digital test which came back pregnant 1-2 weeks - (which confirmed what I was thinking I had taken a couple of dip tests and had v v v v faint line)
I had another clear blue digital test here and just took it out of curiosity to se rid it would say 2-3 or still be 1-2
But came back saying not pregnant? 
I have done a dip one and there's still a faint line?
I would of thought my hormones would of increased by now?  I have drank a lot of water today but surely that wouldn't falter the test?
Please give advice 🙈