So, what else are like the symptoms of bipolar disorder?

Bipolar. Organic mood disorders, cyclothymic do, substance induced mood disorders, schizoaffective do, some personality disorders, adolescent depression & borderline personality.
Many things. Thyroid or other hormonal problems should be ruled out. Drug use, especially stimulants, can cause a similar pattern of mood fluctuation. Add and bipolar disorder can be difficult to differentiate at times or may both occur together. Other psychiatric disorders may cause similar symptoms. The specific timing of the symptoms and longitudinal history are crucial for the diagnosis.