I'm sorry, I wish I could do something to help. Its impossible for me to physically be there for you obviously. If you feel as if you are a threat to yourself, then you should go to the hospital. However, if this has happened before and you calmed down, then all I can say is to ride it out as best as you can, distract yourself, and simply wait until it passes.
I really hope you feel better.
I really hope you feel better.