Teenage Babita is Left handed, which you can see the way she claps during Geeta's Dangal matches. But becomes right handed when she gets older, which you can see the way she claps in Geeta's Commonwealth games.
In the beginning of the movie, there is a wrestling match between Aamir Khan and Vivan Bhatena in the office. When Vivan gets defeated, then he says to Aamir Khan that "you are good because you have defeated a state level champion". To that Aamir Khan replies that "dont feel bad as you are been defeated by a national level champion". Its quite surprising that how come a state level player cannot identify a national level player especially when both belong to Haryana as apparent by their accent.