Ok, thankfully I had a replica server running that I could recover my data from.
In total I lost 9 hours of server uptime while I was asleep.
This has damaged my reputation and I'm extremely unhappy about this.
Google described this as a beta so I knew there would be some downtime. But not fatal errors that could have lost my entire database.
This was only my second day with Second Generation and I experienced 2 huge problems. There should be warning labels all over this thing.
WARNING - UNSTABLE ENVIRONMENT - RISK OF DATABASE LOSS
I'm now downgraded to first generation. I pray it's more stable.