The first thing I would recommend is rebooting your droplet. Then see if you are able to access it via the console (or via ssh). If not, you will want to open a ticket with our support team. They can mount a recovery ISO which will allow you to access your droplet's filesystem via the console to investigate further. It's nearly impossible to tell you exactly what the issue is until you regain access to the droplet to get a look at your logs.