taking the pill 6 hours later

Yesterday i had unprotected sex but we were careful and he pulled out and I took the pill after that at the time I was supposed to. Today my phone died so the alarm didn't work and I ended up taking the pill (combined) almost 6 hours later than usual. I'm on the 2nd week of the pack. Should I be worried?

I don't even know how I forgot to take it, it never happens. I know I'm probably fine, I just need a second opinion to ease my worries

thanks