Sadgirl
During the manic episode I had, when it turned into a psychosis state, I also heard voices. It is common, as you are not alone with that aspect of the illness. Many people with Bipolar Disorder hear voices- some during psychosis or during hallucinations; it just varies from each individual as we all are different.
Depression is a unique illness. It brings about such meloncholy to ones self and drama to the home life, along with much confusion as well. Depression hurts in all ways of life. That is very evident with Bipolar Disorder. There are so many people with the illness that could relate to this theory.
Medicine and therapy are a combination that work well together to help aide in getting a person to stability. Stability is where a person with a mental illness wants to strive for in their life. It is possible, and there are many here who can attest to that.

Believe in yourself, the medicine, the doctors who work with you, the therapists, and your family/friends for support. It all goes together, and if you help it work together as one, things will fall into place.
You are fortunate to have been diagnosed so young. That is a good thing to be treated at a young age. The earlier treated with the illness the better prognosis for a person when they get older for medicine and their illness. Be honest with the doctors because the more honest you are with them, the better they can treat you as a patient to help you get better and have a healthy, happy, and more obtainable life.
Keep posting here. You will learn a lot about the illness by doing so.
Blessings
Coffeegirl