McMillan earned High School All-America accolades by finishing third in the long jump with a leap of 19 ft 4ins at the 2005 Nike Outdoor Nationals.

[1] She compiled 4 Big XII Championships and set two school records, graduating as the most accomplished heptathlete in Nebraska Cornhuskers history.

McMillan placed fourth in Heptathlon at 2010 NCAA Division I Outdoor Track and Field Championships scoring 5583 points.

On June 20, 2015, McMillan scored 5601 points to place fifth overall in women's heptathlon at the Pan American Combined Events Cup.

[8] In the 2015–2016 school year, McMillan trained and coached at University of Dayton in preparation for U.S. Olympic trials on July 10, 2016.