I can sympathize with your fustration, I too have been made to feel like a terrible mother, when my girls have been out of sorts, you are right on the surface everything looks normal. I have been told my DD is spoiled and should be spanked by total strangers, meanwhile she is trying to pull it together in a mall with all the lights, people, smells and sounds. When ohne woman commented I explained she had autism and the expirence was overwhelming for her and she said, doesn't that embarass her for you to say that, most people have no idea what autism means, they've heard the word by have no idea what it actually is, or they automatically assume she is like rain man and a savant.
We have a book we put together every year to explain to the peers in her class what autism and every year we give them more information and a better understanding. So far this has been a success we read it in the first week of school, while DD is away with her aide and then hold a Q&A session for the kids so they can ask anything that is on their mind. I wish I could do the same for adults.
More often then not the classroom teacher doesn't really even understand what autism is and by the end of the year we have gained another advocate. Knowledge is powerful use it to your advantage, tell the pharmacy why you need the melatonin, she would probably handle the situation with much more grace and understanding.
Emmie is my dog is case you were wondering :)
Wanna read my Diary?
Diaries Of A Stamper