am not sure about the specific laws in your country but most countries you have to be in immediate danger of causing harm to yourself or others. all you have to do is say that you aren't going to do it, and have no plans of suicide

old scars mean you hurt yourself in the past, while that is a predictor of future self harm, it is not enough to be able to force you to go to hospital as it is not evidence that you are in imminent danger.

i can understand you being embarrassed, it it were me I'd try to wear something that I could expose my chest with while keeping my tummy covered, even if it was really high pants which look bad but you have to do what you need to. Even in the medical profession there is still a stigma against those who cut