I know you are looking for positive experiences, but I just thought I'd share my thoughts with you, hoping that my torture will help you in some way. I am only on cycle 3 TTC #1, so I don't have much experience and I've never had a BFP. The past two cycles I've been obsessively testing from 8DPO until the day of my period, all stark white BFN! I kept telling myself that "it's too early" or browsing Mumsnet looking for women who had a negative at xDPO and then a positive. Every day, most of the day, it was consuming. I guess the point I'm trying to make is if you test early, all you're doing is peeing on a fiver (or however much the HPT cost). Because, really, you are not looking for confirmation of the pregnancy, as AF is not late yet, but rather you're looking for a BFP. And you won't really accept any other result. If it's a BFN, well, it's too early. If there's a hint of a line, you'll look at the test under every single different light in the house, take it apart, take photos of it, invert the colours, increase the contrast, post it here, pray that someone else sees what you see. And then you'll pee on more and more fivers, your heart breaking a little at a time when a line doesn't appear.
It sounds harsh but I don't mean to. I'm writing this first of all so I can read it again and again and save myself some pain in a few weeks time -hopefully, though I doubt it!
I'm sure there are a lot of people who got a BFN early on and then a BFP closer to AF or shortly after. Some women didn't get their BFP until 14, 20, 25 etc DPO. But these women actually ovulated later than they thought. Viable pregnancies implant between 6-11DPO. Research has shown that implantation after this timeframe has almost 0% of producing a viable pregnancy.
For others, including myself, a BFN was a BFN and never turned into anything else. The truth is, you don't know until AF arrives -or not.
I sincerely hope you get your BFP soon and that a sticky bean is making themselves home inside you as we speak! Best of luck! 