Aheta, you have some valid concerns . You may find answers on the forums that are most closely related to the topics with which you voiced concern. http://forums.psychcentral.com

Your area of concern
1. I can't talk to anyone.
Here is an article about seeing what your mental health care provider will keep confidential for teenage clients
A Teenager?s Confidentiality | World of Psychology

2. Self-loathing.
Self esteem issues are a problem with most everyone here at Psych Central (PC) Being told not to talk about it is a barrier. That is why PC is here to provide an open and frank discussion of issues that are on our minds. Here are some articles on the topic.
Psych Central - Search results for Self-loathing

3. School and motivation.
School is hard. It is really difficult when you see the problems piling up and people won't let you ask the questions and offer to help with solutions. But the problem in ignoring school may be hurting the future. And cutting down the available options. Plus it could make things harder down the road when you want a career that is meaningful and will fulfill your innermost needs plus support a life style where you can get the help you need.

4. I am sorry you have strong feelings about self harm. [self harm or self injury are abbreviated SI or SH] I am glad you have respect for the pain it would cause family and friends. It also would be very disheartening to us at PC also. I consider people here as family and I don't want to let them down either.
Here is a forum that may lend more light to the subject
Self Injury - Forums at Psych Central

Just consider us to be here for you. We are volunteers and we may not be online when you are, but if you post someone will respond. Or private message us and you will here as soon as we get back.

Here is info on having a safety plan. I hope you would never have to use it, but it is best to have one if you have strong feelings about self harming
Self Harm Safety Plans | Channel N

Please let us know your concerns - you do matter here at PC.