I am bipolar and very rarely have episodes that last that long. It's called rapid-cycling bipolar. I've been diagnosed with it for about 4 years and things are getting a lot better with proper meds. Most of my episodes last a day or two at most. But I'm coming off a depression that lasted about 2 weeks. It was horrible. It is also possible to be in what is called a mixed state. Mixed states are different for everyone but for me they include inward feelings of hopelessness and depression but outside I'm going a mile a minute and I can't slow down or sleep. Then sometimes it goes the other way where my actions are depressed but my thoughts won't slow down long enough for me to act on them. Hope this helps!
Nicole