This website was helpful for me in looking at the difference between Manic (bipolar) and depression:

Read more [0] about the common problem of misdiagnosis.

An incorrect diagnosis can lead to inappropriate treatment. In fact, antidepressant medications can bring about a manic episode in someone who really has bipolar disorder.

Awareness about bipolar disorder is the first step to recognizing possible signs. There are excellent treatments for both depression and bipolar disorder. The key is to get a correct diagnosis.

http://www.isitreallydepression.com/mini_c/isitreallydepression/depvsbpolar.asp [1]