If i didn't pay the correction fee stil my previous 1st application is valid or not ???
It is always advisable that before entering all your details do check the fillings twice so that there shouldn't be any mistakes. Once form is filled, correction window is open for the candidates to modify their forms.
if you application form is showing to pay, then do pay it or else your application may not be accepted. If you still have doubts, then do mail the concern to the helpline mail id.