Clare, What drugs are you on?
Did you go to the doctor or the UK version of the ER? How are you feeling now? Has this ever happened before?
Don't assume anything! What you are describing could be other things, such as anaphylaxis. You really need to call your neuro and see a primary doctor (since they do different things). If this ever happens again, you need to go directly to a hospital for care. There's really no way to tell unless they do tests to say what happened.
Please let us know how you are doing! A primary doctor really needs to check on your kidney/liver function as well. A CPK would be useful.
I hope you're ok!!!
Annie