My google site was unavailable

I was greatly surprised that google site was unable to access this morning! When I was going to upload some related information for my students to our course site, I tried one time after another, but unavailable. What's wrong? A hiker riding a trojan horse to attack my site was my first impression. Is it meaningful or worthwhile? I gave a nagative answer. What it might be?I used google engine to search google site, also unaccessible. Ok, maybe google is in a mass just as I have been for these days: unstable blood pressure, lots of things to do, under pressure. Anyway, mine have improved a lot, everything is on its way, going! When will google site recover from his illness?