First day of my first year teaching and I overslept

I graduated last fall and started at a new school an hour away from my house. Today was the first day of school and I was up late working on my presentation for the morning. My phone died and my alarms didn't go off. I woke up an hour after school had started and was 2 hours late to school. I'm panicking and I can't believe I made such as stupid mistake. Is this the end of my career? Can I come back from this? What should I do? When they called I accidentally told them the truth that I overslept.