What do I do about this?

Some stuff happened at a family picnic today (too long to explain) and the aunt who wanted to talk to me more about helping me with the eating issues and getting help ended up mad at me for something unrelated to that. We never ended up talking about it. Because of that, I ended up binging and purging on stuff at the picnic. NO ONE NOTICED WHATSOEVER. How can you not hear a person throwing up?