Whether or not you're bipolar, your mood changes aren't silly. It's terrible being at the mercy of your mood, something we can all relate to. If your miserable days are frequent and extreme, you should talk with a mental health professional or your doctor. Just get screened. It may be bipolar, it may be depression, but you'll feel better if you get treatment.
Under the "bipolar disorder resources" thread, you'll find links to sites which will tell you about bipolar disorder. They may help you think about whether or not you have it. But don't worry yourself sick. It's better to just get screened and find out for sure.
Co-Moderator, Bipolar Forum
"Bipolar disorder can be a great teacher. It's a challenge, but it can set you up to be able to do almost anything else in your life." - CARRIE FISHER