His performances for St Mirren during 2008–09 led to many teams watching Dorman with a view to bringing him into their side. Teams known to be interested included Rangers, Sheffield United and Bolton Wanderers. Dorman's contract with St Mirren included a club option of an extra year, which was exercised in March 2009 after he was voted Scottish Premier League player of the month for February 2009 and another player of the month for April 2009. Dorman spoke out about his transfer speculation, stating that he doesn't pay attention to the rumours and insists he's happy at St Mirren, while manager Gus MacPherson said he would only let Dorman leave for £1 million. Dorman finished the season as St Mirren's joint top scorer (with Billy Mehmet) with 12 goals each.
Although Dorman considers himself to be Welsh, he was not eligible to play for Wales as he was born in England and none of his parents or grandparents were born in Wales. In October 2009, however, FIFA ratified changes which allow players with 5 years compulsory education in a country before the age of 16 to represent that country, which made Dorman eligible to represent Wales. Dorman was included in the squad to play against Scotland on 14 November 2009 when, ironically, he was playing his club football for Scottish team St Mirren. Wales won 3–0, but he stayed on the bench for the whole game. Dorman made his debut for the Wales national football team on 23 May 2010 against Croatia at the Stadion Gradski.