Blizzard is doing some back end database work which tripped a flag on your account. That was a Blizzard quote in the post above. If you click it you can see the Blue posts in the same type threads from the past few hours.
Early Monday everything will be down from 6am Pacific to around 12pm, including the Shop. I would guess whatever they are doing right now with the database is related to the work they are prepping for Monday.