Abhishek, please let me know which exam's fee payment you are talking about. At times, it takes some time (ranging from few hours to 2-3 days) to show the status as Paid. Nevertheless you can confirm the payment status by contacting the exam conducting authority, quoting your application number and they will let you know the status.

In case the amount could not be paid due to some technical issues, you can contact your bank quoting your transaction receipt number. If there was some issue, they will notify you and refund the amount in a few days. You can then pay the application fees again.

Although I believe the status would be updated in around 2 days and you need not worry. Yet you can contact the exam conducting authority to assure once.