Randomly lost all characters?

So, I've been playing since launch, with 2 characters above 80 and a heap of items, runes etc.

I did a trade today, switching from EU to US region. Logged in, did the trade. Logged back out after it was done. Switched region to Europe, aaand my character list is empty.

I tried switching back to US aswell to check, and its also empty there.

I'm getting scared guys.. Anyone experienced this? Game seems to take a long time to load on startup, so I'm hoping its a backend issue.

Edit: Thanks all. Just server issues it seems.