Pakistan and India both got independence from the Britain in the year of 1947.
India declared Hindi as its official language and was able to establish it with almost no or minimal problem.
On the other hand, Pakistan was created with mutual understanding between East and West (Muhammad Ali Jinnah was from West Pakistan and Sir Nawab Salimullah, the founder of Muslim League was from East Pakistan). But when, in 1952, Pakistan declared Urdu as the official language of Pakistan, it was opposed with huge movement.
My question is, why the people of East Pakistan decided to revolt so early (within 5 years of the establishment of Pakistan) when they had a history of mutual understanding with the West?
What factors changed the minds of the people of East Pakistan only within 5 years?
What factors made Indian people not to change their mind?
Please, emphasize on the 5 years of span of time.
Please avoid personal comments and emotions when answering this question. Only facts along with reference web-links.