all mammals. humans and dogs. can have food intolerances. seaweed is really not a part of a dog's diet so i don't feel that it will hurt her but perhaps you should stick with more traditional foods from now on. maybe some dogs can eat seaweed (like those in japan) but your dog's gastrointestinal tract seemed to react poorly. dogs will eat just about anything (one of ours ate a whole pumpkin pie that was left in her reach) but that does not they should. clearly something did not agree with your little dog. i assume she is fine today.
can small dogs eat seaweed soup with small hunks of beef in it? . i fed our bichon about a quarter cup of it and she woke me up at midnight wanting to go out side very badly and it was obvious when she came back in she had the runs.