Pregmate strips warning

I started using the pregmate brand opk strips this month right after my period and only had two negative results before I got a positive on cd9. Today was the seventh day of getting a positive and I thought something was wrong with me! I tried a first response opk at the same time today and the pregmate was of course positive while the first response was negative. I know some people have luck with these but I won’t be using them again after all the false positives.

Anyone recommend another brand? I heard wondfo was reasonably priced.