Normal? I'm just afraid...

Good morning! So, I have a question. I tested Monday morning and there was a very, very, very faint line for a positive there. I keep getting told to test on Saturday (which I plan to do), but I'm so afraid that it's going to be a negative test. Is this normal? If it winds up being a positive (like fiancé and I are praying it is), this will be our first (period, neither of us have any other children). I'm just so afraid of getting another negative...