Nengmin Wu, 34, from Dublin, admitted driving at 78 mph on the 60 limit A75 road near the Terregles overbridge on October 3 and with a driving licence relating to someone else.
He also admitted entering the UK without a visa.
The court was told that Wu had been in Southern Ireland for some time and was working there in the restaurant business.
He had been stopped and given a speeding ticket by police at the Dumfries road and then it was found a few hours later at the ferry terminal that he had no visa, but a valid passport in his own name.
A solicitor said that Wu had been visiting his brother in Newcastle and when stopped by police had thought he was in danger of missing the ferry.
He also had five points endorsed on his licence.