The 25-year-old hit the third goal in Scotland's 3-0 win over the Faroe Islands at Pittodrie.
"I'm absolutely buzzing," he told Rangers' official website. "It's a massive achievement for me and hopefully the first of many at this level.
"There's an element of pressure when you come into the squad because you're asked to perform. I wanted to show everyone what I'm about to make sure I stay in the squad.
"The pressure is from myself and I'm pleased with how I did."
Source: PA
Source: PA