Random Depression.

Can you help me? i'm fourteen years old. I was sitting in my room earlier. I then felt.... trapped. Like i couldn't get out of here, but my blinds were open and my door was right there... I thought I should just lay down. A minuet later I felt tears in my eyes and thoughts of all the bad things going on in life. I tried thinking of the happy points of views but i just couldn't. i have an amazing boyfriend and a few close friends and like 5 just friends. And i thought life was okay.. but i couldn't stop the tears.. I don't know what i feel.. I just want to know what is happening..