Pregnant?

So first let me say I know how getting pregnant works. I have three kids. 11, 9 and our rainbow baby is 11 months. I've been taking birth control BUT with three kids who knows if I missed or or what?? So my period is late. Last period was Dec 7. I mean I could totally be pregnant right? I've never even known this early. I always found out with my others when I got sick... I knew. We were not ready for another baby. I'm still dealing with postpartum depression from this one. We tried for 7 years to get pregnant with our last and lost a baby in there too. I still have a test left over from last year. Is it too early to take a digital test? I think the panic is clogging my brain!