I got a BFN 11 dpo and a BFP on 17 dpo so I think the longer you wait, the better. (I didn't test in between those dates so I might have gotten a BFP sooner)
Ps if you go to pee on a stick .com it gives you a list of the different brands and what their tests require for a pos hpt! So that should help you too!
AP
I got a positive 11 DPO, four days before my period was due. I use First Response Early Result. The digital ones aren't as sensitive, and the blue dye ones seem to give false positives or have "ghost lines".
I got my first positive 9 days before my period was due. I took another it was negative took two more positive and then had my blood drawn and it was positive so it depends on how high your hcg levels are. I too tested early due to ttc for 4yrs. I had reoccuring m/cs. Good luck.
I got my positive 10 days after Ovulation. If you get the early preg tests they can test up to 5 days before your period is due...however it is most accurate if you wait until at least the day you are due. I was doing all the early testing because we had been trying to conceive for 7 months.
14 days after sex is the earliest you usually can get a result. It takes a week for the baby to implant then another week for hormone levels to be high enough to detect.