possibly pregnant

Debra
I stopped my birth control a month an a half ago my last period was normal this month I was suppose to have a period last week I've taken 2 preganancy test one had a line with a second faint line the other was negative what should I do to make sure if it's positive or negative? my fiancé and I really want children but we're scared that we can't have them. help extremely worried. Unsure