I'm probably completely overreacting here and am quite prepared to be told so 
I put a comment on Facebook about a lovely note from school about my son (he has sen and finds school difficult) saying he had worked really hard today.
I spelt hear wrong (I spelt it here, one of those words I get confused with!)
My SIL then commented I had spelt it wrong, I know it was probably a joke, and wouldn't be so bad if it was a well done as well, but no, just taking the piss out of my spelling.
I'm still proud of him, but feeling annoyed with the comment as it kind of takes the shine off. She has obviously never heard if you don't have anything nice to say!
Please feel free to pass me a grip 