Hello and thank you for the request.
Did you tell your therapist that you intended on hurting yourself? If you said that you have a plan and told your therapist what it was, she can have you evaluated by filing for a 302. A 302 is a legal document that can force you to have an evaluation done. It does not force you into the hospital unless the ER doctor feels your evaluation warrants you being admitted. For example, if you felt suicidal when you talked to your therapist but have since then felt better and no longer feel suicidal at the time of your evaluation, you will probably not be admitted. You have to be in imminent danger of hurting yourself, someone else or of failing to care for yourself to the point that you are in danger of becoming ill or dying. If you are found to have any of these conditions, you can be admitted against your will. You can be held for 72 hours. Once the 72 hours are over, there would need to be another hearing by a judge in order to hold you any longer.
You can choose to override the 302 (before you are evaluated) by admitting yourself on a 201. On a 201, you can leave voluntarily at any time. The only way you could be forced to stay is if someone files a 302 and they show good cause to be concerned about your condition.
Your therapist is not allowed to share any information about your therapy, including confirming that you are a patient, unless you sign release forms allowing her to share. These forms may need to be updated every year and you have the right to revoke them at any time. You may want to talk to your therapist about revoking her rights to share if you have the confidentiality forms already signed. At your age, your parents should not be contacted unless the are an integral part of your therapy or you are in such danger that you cannot care for yourself and your parents need to be involved to help you.
Anyone can file a 302 on you. But it is only good for an evaluation at the hospital. If the examiner and the doctor do not agree that the 302 holds any fact, they can release you. The 72 hour hold is to offer you treatment and see if your symptoms subside. If they do not, your stay at the hospital is recommended to be extended, hence the hearing with the judge. That just means you would stay longer at the hospital, not be transferred to a state hospital.
Wanting to die means you feel suicidal. Your therapist is greatly concerned about your condition if she is talking about filing a 302. I imagine she feels enough concern about your welfare to try any means to get you help. She is not only mandated to do so, but she feels for you and cares about you. There is help out there so you do not have to feel this way, and she is trying to help you get it.