I am sure this was very frightening for you. I would guess this is situational and will likely leave on its own. If not then you would need to talk to Dr. if it persists or gets worse. You could try relaxation techniques as you are trying to go to sleep. There are a bunch of different ones and a quick search would probably turn some up quickly. Or someone will likely give you an url directly to a site soon.

I hope you are feeling better soon.

Take care.

place