Tumwa started his career at
Watford, and in February 2012 was loaned to
Isthmian Premier Division side
Harrow Borough while still a second-year scholar. He signed a one-year professional deal in summer 2012 at the end of his two-year scholarship. The following season, he again spent time on loan in the Isthmian Premier Division, joining
Wealdstone from the beginning of November 2012 to late January 2013. He was released by Watford in summer 2013 having not played a game for the first-team. Tumwa subsequently joined another
Championship club,
Blackburn Rovers, in August 2013, joining their development team. He was released in May 2014 having not played a game for the first-team. In August 2014 Tumwa signed for
Conference South club
Farnborough. In July 2015 Tumwa signed for
Conference National club
Bromley. After making five league appearances, he joined
Hayes & Yeading United on loan in March 2016. In June 2016 he joined
Margate. ==International career==