BFP then BFN next day!?

[1997Babyx]

Hi all
I took a pregnancy test (around 9dpo but that's only based on ewcm and cramping - I don't 'properly' track my ovulation!) last night at about 9pm, and got a very faint blue line which then darkened to a very obvious blue line after about 10 mins!!
Was so excited... then this morning I used e exact same brand of test - clear blue ultra early - this morning at about 5.30am on fmu and got a bfn!! Can't even see a faint line :(
Has anyone experienced this before?
I have ordered some pink line tests but looking for advice - is my hoping just hopeless :(
Thanks

You should only count a line which shows within the first few minutes. It may just be a little early to test, try doing another in a few days. Good luck

At least there was the faintest of positives after 3 minutes!

Thanks for the luck .. now just the pain of waiting to test again!!