Best known for his time spent in Australia, Carlwell is a two-time SBL champion, having won his first in 2012 with the Cockburn Cougars and his second in 2018 with the Perry Lakes Hawks.

As a junior playing for the Proviso East Pirates basketball team in 2004–05, Carlwell was an all-state choice after averaging 15 points, 12 rebounds and six blocks per game.

He averaged 18.8 points, 12.4 rebounds and 5.4 blocks as a senior en route to earning West Suburban Gold Conference MVP honors.

[1] As a freshman at Illinois in 2006–07, Carlwell played in 26 games before missing the final eight contests due to head injuries sustained in an alcohol-related crash during a severe blizzard.

[2] Carlwell averaged 1.7 points and 1.4 rebounds in 7.0 minutes in his freshman year, as Illinois finished 23–12 and advanced to the NCAA Tournament where they lost their first-round game to Virginia Tech.

[8][10] In his two-year career at San Diego State, he played in all 71 games, starting four times, and averaged 4.2 points, on 56.5 percent shooting, and 2.7 rebounds.

[11][12] He made his debut for the Cougars in the team's season opener on March 17, recording 27 points, 16 rebounds and four blocks in a 91–88 loss to the Perth Redbacks.

[16] The Cougars went to advance through to the SBL Grand Final, where they defeated the East Perth Eagles 105–72 to win the championship behind Carlwell's 21 points.

[32] He made his debut for the Bulls in the team's season opener on October 5, scoring 11 points in a 68–53 loss to Aomori Wat's.

[33] In the team's fourth game of the season on October 13, he recorded a double-double with 10 points and 10 rebounds in a 75–61 win over Niigata Albirex BB.

[36] After taking time away from the game to focus on starting a new family, Carlwell returned to the SBL in 2016 and joined the Perry Lakes Hawks.

[37] In his fourth game for the Hawks on April 9, Carlwell recorded 20 points and 21 rebounds in a 100–94 overtime loss to the Stirling Senators.

[41] In the Hawks' regular-season finale on July 29, Carlwell had his fourth 20/20 game of the season with 26 points and 20 rebounds in a 102–96 win over the Suns.

[61] In January 2023, Carlwell joined the Kalamunda Eastern Suns men's team as an assistant coach for the 2023 NBL1 West season.

[64] On February 12, 2007, Carlwell suffered a severe concussion when the car he was travelling in, driven by inebriated teammate Jamar Smith, slammed into a tree on an icy road in Champaign, Illinois.

[65][66] Upon arriving back at the apartment complex, residents called 9-1-1; Carlwell was taken to Carle Foundation Hospital in nearby Urbana where he was initially listed in critical condition.