I think the only way to be sure, diagnostic wise, if you have depression is a mental health professional. But, considering you present with many symptoms it may be an issue. Also, the issue may be the family negativity and judging of you, which can create anxiety, depression, and lack of self-esteem.

If psychology interest you go for it. Many people enter psychology because they have some type of personal experience with mental health or illness, familial or self. Some enter it just to help.

To tell you the truth, in college most of the psychology classes taken have nothing to do with abnormal psychology (mental illness). PSY 101 glosses over, an abnormal psych course is definitely all mental illness, and a few classes have some mental health issues mixed in (Criminal behavior or intro to clinical counseling); but, the majority of your classes have to deal with social psychology, experimental methods, statistics, psychology of different groups of populations, history of psych, behavior modification, etc.

In the end, find a major you love. A subject that will fascinate you for years down the road, not just now or for 5 years. Realize that whether or not your parents approve, you are the only person who can discover your happiness. Your parents will either get over the initial disappointment of you not doing what they want or they can be miserable, don't let their unhappiness effect the ability for you to achieve to your happiness.

Don't feel the need to commit right away, use the first year of college to explore a variety of fields. I was a Elementary/Special Ed major and switched because I needed to be happy.

Lastly, once you get to college if you need to go to the campus counseling center, go. Your parents won't know and it will be a place to vent and get help.