Trump as usual is playing the media for his own gain. True his outrageous claim regarding millions of illegal votes is patently false, but this nonsense deflects interest away from the New York Times story about his international business and their potential conflicts. 
Trump does whatever he pleases regardless of what " protocols " normally dictate. His business interests are as important, if not more so than his presidency. That the NY Times would investigate his business conflicts probably incites his irrationally to greater heights than calling him a poor president. 
This twitter outburst was for his base . Mission accomplished.