Anyone know what this error means?

WordPress database error: [User ‘my actual SQLdatabase username here’ has exceeded the ‘max_questions’ resource (current value: 50000)]
SELECT FOUND_ROWS()
—————–

All was running well with my blog until two days ago when the site began slowing down dramatically. One day ago the site would barely load at all. Today, the site loads slowly, but acceptable speed – but I get database errors (I assume) everywhere.

I can login to the admin area, but can’t turn on/off any preferences, can’t enter posts, etc… I get the error above on every page I load.

Anyone have any idea what this could be? It’s happened once before, but it happened just after the 2.0 upgrade so I thought I had done something wrong. This time, all was running smoothly and I wasn’t even posting when it happened.