Hello Lokesh,

Generally while filling application forms for various entrance exams through online mode, you can make the payment through a number of ways. If you pay through online mode, i.e, debit/credit card or net banking, then the status is generally displayed as as paid almost instatnly unless if there is some delay from the server. The other option would be to submit via an e- challan where you have to submit the amount in the listed banks and upload the proof receipt. 

If you still have some problem, then get your passbook completed and there should be a transaction id in the passbook for the transaction of the entrance exam.