Relax, take it one hour/day at a time. Try to build a list of people you can contact for support if needed, I imagine you and your boss aren't the entire IT team. If something happens and you get stuck call someone, its ok (especially as an intern) to say 'I don't know I need some help' especially if something is on fire. Try to find or define a plan of what's going to happen, eg at X time someone will start the roll…
thanks for the kind words. helps a lot.