Your PM is saying that you might get angry or exasperated with him, but he recommends the work to be ready much sooner than he probably thinks you expected, (when you've done so much already). It may be intended as self-irony in a humorous way. So basically, read it as, Sorry to stress you you even more, but... hurry up.
To throw a/one's show at someone is an expression used to show protest, and we have seen incidents in different Parliaments of the world where this was not an expression, but a real gesture which can even involve both shoes as you can see that it happened to Bush (see link). About this expression, Wikipedia says:
Shoe-throwing, or shoeing, showing the sole of one's shoe or using
shoes to insult are forms of protest in many parts of the world.
Shoe-throwing as an insult dates back to ancient times, being
mentioned in verse 8 of Psalm 60 [over Edom will I cast out my shoe] and the similar verse 9 of Psalm 108
in the Old Testament. Modern incidents where shoes were thrown at
political figures have taken place in Australia, India, Ireland,
Taiwan, Hong Kong, Pakistan, the United Kingdom, the United States,
and most notably the Arab world.
It's interesting to see how this expression was used for a long time with relatively the same frequency on both sides of the ocean, but has recently known a decline in the UK.