Donald Trump himself is a disaster and anything that comes out of his mouth is a disaster. He has created so much hatred and he has told so many lies that it is very difficult to believe anything that he says. People should be focusing more on his actions than his words and only then we will have any idea whether he was telling the truth.
Trump did not come off as professional or presidential in any way. He let his emotions get the best of him and he caused a major scene, which is not what we need in a leader. He proved that he does not have the poise and ability to remain calm that is necessary to be the president.
While certainly Trump's press conference deviated from what we are use to, I would not categorize it as a disaster. He followed his usual script and made it clear that his election to the presidency is not going to change how he presents himself. However, his attack on news outlets may prove unwise later on down the line for Trump.
No, Donald Trump's first press conference was not a disaster. He did just what he wanted. He got up, made a spectacle, answered the call for holding a press conference and said what he wanted to say. The press will have a harder time dogging him about his media relations. Trump was in all the headlines again. Trump supporters have some lines to quote and hold onto when trying to blindly defend him.