Nts exam takes place every month perhaps, if you were willing to apply in a university on basis of nts then it depends on the admission date of the university. Just take the next test if u missed the previous one, you needed to keep at pace with the dates. Now you can apply in the entry test of the university and take their test directly. If there are some universities left, which of course interest you, then register in the next nts exam, im sure it'll work out for you.