West Bromwich put up a spirited performance and took the fight to Mourinho's men.
However, the United manager also gave a strong defence of his own record, listing some of his achievements with Chelsea, Real Madrid and Porto, after being asked how United could expect to overhaul Pep Guardiola's team next season.
Last Saturday goals from Paul Pogba and Chris Smalling handed United a 3-2 comeback win in the Manchester Derby.
"They were the right ones and the ones we believed in, I'm sure there are differences to how we play today compared to Bayern (Munich) and Barcelona, we survive and live by the strength of the team".
'We deserve top be punished, but the defeat was too heavy'.
"I have won titles, I would not be happy if someone said I won title because someone lost a match".
'City were the best team, sooner or later they would get the points, so no dramas when the best team wins the league'.
United face West Brom and Bournemouth in the Premier League before their FA Cup semifinal with Tottenham at Wembley next weekend.
Guardiola's men were close to securing the silverware faster than any club in the competition's history, falling short of the April 14 mark set by United in 2000-01 by a single day.
Mourinho added: "We have a big game next weekend in the FA Cup against Spurs, but our focus has to be on three points in a hard game against a team fighting for Premier League survival".
The France global has blown hot and cold at Old Trafford this term but produced an unforgettable performance in last weekend's Manchester derby to help the Red Devils overturn a 2-0 deficit to win 3-2.