[Usernames Suck]

First of all, congrats on reaching the point where you're ready to tell someone. I think it's a good idea, and the odds are that your teacher won't hate you for it.

There may be policies in place that may require your teacher to report back to your school's counsellor or even to your parents. The best way to figure this out is by asking him straight away how much he's required to report and to whom. It's also a good idea to ask what subjects would warrant reporting, for example, telling him about your anxiety may not need to be reported but talking about self-injury might. Asking him beforehand is a good way to make sure, as he'll then be able to let you know what the policy is and you can decide based on that.

Even if you don't wish to tell him about self-injuring, it could still be a good idea to tell him about your anxiety and depression. He may be able to help you find resources, ways to cope, and even professional help if you need it. If he does have to tell your parents that, it may help if they hear from an authority figure who is on your side.

I'd also recommend telling him how he can help, if you know of anything specific that would help. For example, are you looking for affordable professional help? Are you just looking for someone to talk to? Are you looking for help researching coping mechanisms and options available to you? Knowing this could help him help you, even if all you've got to say is just that you want to talk to an adult who won't tell anyone.

Best of luck to you and feel free to message me if you ever need help or just to rant.