Sir i had blood in my stool twice today. it is pinkish in color and water liquid state. i am 20 and usually lift heavy weights in gym.can it be cancer?

Very likely NO: Pink, red stool implies that source of blood is toward end of GI tract - i.e. hemorrhoid, anal fissure, distal colitis. If it was coming from further back it would be blacker. If persists see a gastroenterologist.

No: At age 20 the induction of cancer of t he colon is rare since it probably takes a year or two for cancer cells to develop and become symptomatic. Most of the bleeding at your age is do to a fistula or crack in the lining mucosa that starts bleeding or hemortoifds . If problem continues see proctologist.