Need help please

So I took a test about two hours ago and it was a definite faint positive but then took another one about 10 minutes ago to show my husband because I accidentally threw the first one away (and took the trash out) and now it’s negative. Could it be because I just didn’t have enough hcg in my pee and it’s just too early because I’m 7-8 dpo. I know for sure the first one was a positive.