Are these signs of depression?

yes, these are signs of depression and need to be treated. They will not just go away. Tell your parents what you are going through and I'm sure they will help you. You need to talk to an experienced counselor so they can find out why you are going through this. There are medications to help you deal with this. Remember medications do/will help but you need to continue taking what is prescribed for you even if you feel better. With the thoughts you are having its very important to get the help immediately.