Cortijo was born in San Juan, Puerto Rico to Angel Cortijo and Lourdes Sanchez. She grew up in the city of Carolina, Puerto Rico. Cortijo first earned widespread fame for her basketball skills during two seasons of play for Maria Auxiliadora High School, which went undefeated and won the Puerto Rico commonwealth championship both years. Cortijo was named Puerto Rico's High School Basketball Player of the Year for 2002.
After Cortijo's sophomore season, her family moved to the Houston area. Cortijo attracted national attention as a star point guard for Bellaire High School. She also played AAU basketball for the Houston Elite squad, leading them to the 2004 AAU national title. Cortijo earned Parade Magazine All-American honors for her high school play, and was rated the nation's best point guard in her recruiting class by All Star Girls Report. However, she missed her entire high school senior season with an injury to her left knee.
Cortijo signed with the University of Texas. Early in her freshman season, she re-injured her knee, and received a medical redshirt waiver for the 2005–2006 season.
As a redshirt freshman in 2006–2007, Cortijo played in 28 games for the Longhorns and started in 18. She led the team in assists, with 137 on the season. Cortijo was one of five players named to the Big 12 All-Freshman Team and the Big 12 All-Academic First Team.
Cortijo announced during the offseason that she planned to transfer to St. John's University in New York. However, Texas coach Gail Goestenkors eventually persuaded Cortijo to rejoin the Longhorns for the 2007–2008 season.
Cortijo is majoring in Spanish and minoring in textiles.
Cortijo alleged that Puerto Rican basketball federation's president Carlos Beltrán denied her an opportunity to play for the Women's National Basketball Association (WNBA)'s Atlanta Dream in order for her to participate with the Puerto Rican women's national basketball team on the 2015 Edmonton, Canada Women's Pre-Olympic qualifying tournament.
Cortijo represents Puerto Rico in the international competitions sanctioned by FIBA. As regular point guard, she led the team to the gold medal at the 2011 Pan American Games, which advanced to the finals gathering victories over the United States, Argentina and Brazil. In the gold medal game, Cortijo scored 29 points and recovered 10 rebounds, being Puerto Rico's most productive player in the victory over Mexico.
She was a member of the team which competed for Puerto Rico at the 2011 Pan American Games, winning a gold medal.