my parents don't believe i have depression?

While I appreciate that this is a serious question concerning an issue that is rightly important to you, we older types often wish we had not taken everything and everyone (including ourselves) QUITE so very seriously during our short teenage years, so be cool, use humour and your natural warmth - we all have it, but some are frightened to show it. These years (approx. 12 - 21) are a period of emotional change and discovery – so much changes! We can’t avoid changing, but we CAN make decisions about which direction we wish to go in - the sort of person we want to become for example. The important things are to develop self respect and emotional self sufficiency (i.e. not relying too much on someone else for our happiness) and to work on our values and qualities such as integrity and respect for ourselves and others: absolutely everyone has things about them you don’t know about. Also ensure that you have no unnecessary fear (False Evidence Appearing Real!). We CAN decide about and plan our directions by practising in our minds the kind of person we wish and intend to be. Especially first and last thing in the day when the subconscious is most accepting of your conscious thoughts. (So avoid negative t.v., video games, etc., especially at night). 

Life tends to come in seven year stages (or maybe six is the new seven!). Infancy, then childhood then adolescence, which is usually around 12 - 21. Naturally people vary, and the stages merge into each other like the seasons do, but it continues to an extent: many women are not too mature until late 20s and a lot of men don’t even start to grow up until their mid thirties (I was one!).  Actually Judge Judy said recently their forties!

All parents have been teenagers of course, and can be taken back to their teenage feelings with genuine interest and positivity on your part. That said, no one person can ever completely understand another (except identical twins, perhaps): we all come from slightly different places and have different experiences of and takes on life. Hence nobody can judge us with any accuracy. 

Remember: adolescents’ emotions are in a state of flux and constantly changing – some more than others, obviously. 

Look, your parents clearly love you but don't seem to understand how to show it (really - no parents are perfect!). You wrote that they hug you a lot, but they don't understand that although their preferred way of communication is physical, yours isn't.

You do need some help with your problems, so call 1-800-4ACHILD if in the U.S.A., or Childline (0800 1111) in the U.K. No doubt other countries have similar free phone lines. Canada is 1-800-668-6868, Ireland: https://www.childline.ie/.

Good Luck! There are things in your question that shows that there is something about you that shows maturity beyond your years. Please call the help line, though.