You can easily check to see if a donation has gone through to the Payment Gateway by checking for a Transaction ID and Transaction Result on the Online Gift Detail. To view this:
  1.  Navigate to School Website > Content > Giving > Giving Forms
  2.  Select View Online Gifts for the Giving Form
  3.  Click Edit for the transaction in question
If the Transaction has gone through to the Payment Gateway, it will show a Transaction ID. If the payment was received without any problems, the Transaction Result will be Successful.