My advice would be to clarify with him his role with you. Has he told you before that he cannot be available for emergencies/crises? Is he telling you this now? If so, you need to find an alternative, someone who can help you -a T, for example, who is willing to deal with crises in the moment. Once you start DBT, I think you'll be assigned a T you can call. I'm sorry this wasn't clarified earlier and you were under the impression that he was. There seems to have been some miscommunication somewhere along the way.

And since he can't help with crises, yes, I hope you go to the ER. That can at least help you in the now, help you get over this hump, while you wait for DBT, which could help you in the long run.