Store Brand Tests - still accurate?

My husband and I are on vacation with his family and I took a few First Response brand tests before we left even though I wasnt supposed to get my period until the middle of the trip. They were all BPN. We picked up CVS brand first response last night because my period was a day late and I didn't want to spend the extra money for name brand if they were going to be negative. Well, I think these are positive? I don't want to go back to the drugstore and buy more since we don't want his family to know yet. Has anyone had an issue with store brand not being accurate? And is this positive?