I lost my ability to flag. I have no idea why, I assume I flagged one too many posts that ended up as popular. Just as well. One less distraction for me.
I don't think so, not for just flagging but there does seem to be a way HN can find this type of behaviour and ignore the actions of users that abuse the voting system. read this for some more info http://www.jacquesmattheij.com/The+Unofficial+HN+FAQ