when i was pregnant with my first, i had absolutely awful morning sickness. i lost over 20lbs in the first trimester... people were CONSTANTLY giving advice about what i should eat, what i should avoid etc. yes, after 3 months of eating nothing (if i even thought about food, i'd be sick) it started to get annoying as i'd tried everything.
but i NEVER got annoyed with anyone. they were trying to help! so, i'd just smile nicely and say, 'thanks, i'll try that.' and move on....
why get worked up and negative? perhaps they are not meaning to come off as bragging? otherwise, it would be difficult to them to say anything nice about their kids ever...
just for your info: my daughter, i think, is "gifted"... she is extremely bright and bored at kindergarten. her vocabulary, when she chooses to use it is immense. BUT, she has a TERRIBLE temper. she doesn't throw a fit. she pouts and refuses to move, speak, interact at all with anyone. if we were talking about schooling and i mention that mine is bored at school because it's too easy for her.... you would consider it bragging. i wouldn't mention the latter part, because we are talking about schooling.
so, perhaps your child sucks at school, but is a lovely, calm, cool and collected child.... again, if we are talking about schooling and you talk about your child and then i mention mine. you would consider it bragging? if the roles are reversed?
i really think you are reading too much into it. perhaps they thought it was an open and honest discourse on whatever subject you were discussing? did you ever say while talking about the subject...."oh, i just don't know what to do anymore! i've tried everything!" .... if so, maybe they thought you were asking for advice.
in the job that i do, i deal with hundreds of very young kids every week (10m-4yrs). in my capacity, i am constantly being asked for advice and told about difficulties experienced with the children. it's part of my job to offer ideas on how to make it better... doesn't mean i know it all or even that i think i do.... i just have a lot more experience with these ages of children than the average parent has....