All my life im upbeat and cheerful but have low self confidence/anx.can change from happy to sad with ability to hide it. could this still be bipolar?

Why bipolar?: It's not impossible, but too many people seem to think this is their problem. As you note - better self confidence might be a good goal. To do that, a good cbt therapist might really help. You'd learn ways to take action toward building things of value in your life. Learning, doing, sharing - forming relationships and discovering what matters to you are things that will make a difference. Best!

Could be Anxiety DO: To Dr. Weixel’s point, anxiety can also be very distressing but may be a sumptoms of an anxiety disorder rather than bipolar. Cognitive Behavioral Therapy (CBT) can definitely help you reduce and better cope with your anxiety. I would recommend that you talk to a psychologist who can help better determine what is effecting you and develop a treatment plan to help!

Anxiety: Your question is best answered by consulting with a Clinical Psychologist who can help you sort out your feelings and figure out what is happening and how to cope with it. It’s not necessary for you to specify a certain type of treatment. Most important is your comfort level with the Dr. Medication can also be added if needed.

Not necessarily: Many people have minor mood fluctuations during the day that could be precipitated by external or internal triggers but this doesn't mean they have bipolar d/o. The severity & intensity of mood swings along with other symptoms such as impulsivity, racing thoughts, insomnia & extremely inflated self-esteem may indicate it. Sched an appt for an eval with a mental health professional if concerned.