Mercury workflow to tackle sudden priorities

The scenario is that I come to work in the morning and pull, update, merge my mercury tree. Starting with the latest version, I start working on the current problem. I reach a logical milestone and commit. The tree now looks like this:

*  <- my first commit for the day
|
*  <- merge commit from shared repos by team

      

        
        
        
      

    

Now the boss is coming, something terrible has happened and I need my close attention. He wants the solution to be pushed as soon as possible.

My plan for the day is broken. What is the best way to use mercury to solve this problem?

• I could just write a solution and make another commit followed by a push. But this is bad, as this commitment will have my own first commit as parent, resulting in incomplete code.
• In a perfect world, it is possible that the new coding feature Im going to be on its own branch. But its a small feature and Im lazy, which is why it is currently in default
  
  . I could try to find a way to move a commit from one branch to another.
• I could ignore the panicky boss, do two or three attempts at this feature, push, and then start working on the fix by typing them into a separate commit and pushing.

None of them are doing well. I would like something like:

• Do an update, bringing me back to the merge commit.
• Make the correction and commit it.
• Click only the commit commit, leaving the unfinished compilation not pressed yet.

Thus, creating a story like this:

*  <- fix commit (pushed)
|
| *  <- my first commit for the day (unpushed)
|/
*  <- merge commit from shared repos by team

      

        
        
        
      

    

We just moved to Mercurial here in the office, and this is one of the issues that I would like to address. Any mercury gurus here that the mind shares some wisdom?