I know that my ex checked himself into the psych ward more than once. (after a crack binge when he would be in the depths of the pit)
in MN if you are a threat to yourself and it is related to drug use then they keep you safe for a few days and then send you to treatment.
he checked himself in, but I am sure the police would do the same...
desperation can be a good thing
praying for you and your son