You shouldnt be critisizing Rafa.
You have only lost 2 games all season, youre behind the scenes is fucked up, you have a pretty average squad of players (admittedly that he bought, but might not of looking at the Keane transfer), and you are up against a United team who went 14 league games consecutuve without conceeding a single goal.
Your doing aswell as could be expected, and 7 points IS NOTHING.