What Happens If You Go In For A Psych Evaluation And They Tell You You Need To Be Comitted?

Just wondering, what are the laws concerning the situation I am contemplating. I mean, if I let the seed of ideation grow it will become a larger and larger desire to stop this life, so I may decide that I need help stopping myself and go to an ER for what I have always heard called a psych evaluation. If it is determined I am a danger to myself, am i basically under arrest? Do i have any rights to get up and go home? What happens to my job responsibilities, my income, my health insurance,... What Happens If You Go In For A Psych Evaluation And They Tell You You Need To Be Comitted?
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