Yes, you can change your college as well as your course even after taking admission, but you would have to recollect your original documents from the college in which you have 1st taken admission. Your original documents would be released by the specific college but the procedure is hectic and admission officials are not very helpful in case you opt out of their college, which could delay your admission in the other college. So, in my opinion be selective and smart while seeking admission in a specific COllege . so you don't have to worry about changing it again. Good luck.