How do I turn off my laptop?

Last night I shutted down my laptop (or so I thought) and closed it. But this morning, I opened it and it just continued shutting down. So yesterday I obviously closed it before it shutted down. Now it is shutting down for like an hour. I tried to hold start button but nothing happens. I also cannot find the restart hole. I searched every inch for it. Could it not be there? What do I do?