"Honestly, I have been well-tested (over the last week)," the 63-year-old said.
"It is not the critics that have been tough. I'm not masochistic - I prefer that (the media) say I'm good rather than bad, but I can understand that is part of my job.
"What was very, very difficult to take was to lose against Blackburn in the FA Cup at home and after against Bayern, it can go both ways - but one after the other, to lose big games, that is what was absolutely terrible.
"We question ourselves always as coaches. You are not 30 years in your job if you don't question yourself. It is a bit more challenging now. I don't think it is down to the methods of coaching or training or managing the team. Opinions are multiplied by a thousand - everyone knows exactly what you should do, but not everybody has been on a football pitch."