Why did Kangana deliberately hurt herself?

Rajjo is a special film for Kangana Ranaut that why she wants to give her best possibility shot that she can give.
Also the most challenging role she ever played and also feel lucky because this year she got to show audiences two different character that she played films like Kaya for Krrish 3 and Rajjoas a Mujare wali girl.
Rajjo will has given her the opportunity to show her dancing skill and bold dialog delivery. Weather its her looks or her dressing or her Dancing moves or her fighting scene she has given her 100 % to the film like a perfectionist.
While doing one of the fighting sequences Kangana was not able to perform the shot to give real feeling touch for the shot. So she actually hurt herself to give the real feeling pain to the shot of the film. Which marked a great impact on Rajjocrew team seeing her dedication for Rajjo.