Yes you have bipolar
disorder. See a psychiatrist and get meds.
Lamictal, Lithium, and Abilify are good
for starters. They're the most common, safer meds. When you tell your mom that you want to get checked out I would recommend not mentioning the bipolar thing. A lot of parents don't believe that their children have such a disorder. Just tell her that you're sad and want someone to talk to that has an unbiased opinion.