positive pregnancy test vs different pregnancies

I have always gotten positive pregnancy tests before my missed period for all my pregnancies. Have any of you gotten a positive pregnancy test before your missed period with one pregnancy and then wasn't able to get a positive until the day of or after your period with another pregnancy? I just need a little hope..my period should be here tomorrow I took a pregnancy test yesterday and it was negative. I got my surge on cd 15 it only lasted like an hour and then I got another positive OPK on cd 25 got all excited thinking I was gonna get a positive pregnancy test but nope negative...  

Yes. all the dollar test would be positive way before the expensive "brand" names.

I always use dollar store brands. Dollar tree is my favorite.