I was walking DS (11 weeks) round the block in his buggy. I probably looked pretty miserable-I'm not, just sleep deprived and DS (11 weeks) has been alternately feeding and screaming at me non stop all day so I just wanted to get out of the house for a short walk. I walked past a group of pissed blokes standing outside a pub and one of them gave it the old 'give us a smile luv' and I snapped and told him to F off. I feel really annoyed with myself that I let him get the better of me but WHAT is an appropriate reply to this bloody annoying comment?