I feel really depressed and need help but I am embarrassed to reach out for help?

I am 16 years old and know I have been depressed for a while, more likely feeling lonely at night time but this is the worst feeling ever and I know I need help. I want to get professional help but my mother doesn't believe how I really am feeling. She often uses phrases like "drama queen" and she just ignores every time I try to tell her how i feel really depressed. How can I truly get through to her without doing something dramatic? I'm really a smart person and I don't want to harm myself in any way, but I feel worse and worse every day. Any suggestions of things I can do to feel better or how I can talk to my mother.. thank you.