Before playing in the NHL, Regin played 3 seasons with the Herning Blue Fox in the Oddset Ligaen. During his time there, he was named the Rookie of the Year in 2004. He was drafted with the 87th overall pick by the Ottawa Senators in the 2004 NHL Entry Draft. Before playing with the Senators, Regin decided to play another season with Herning and joined Timrå IK in the Elitserien in 2005. He played 3 seasons with them and increased both his goal and point production in each season that he was there.