Painful defecation/ motion with few drops of blood in a young age, may be due to Anal fissure. You need to get treated for that. Avoid hard stools. Take Laxative like Duphalac 15 ml at bedtime.
Next Steps
Consult a surgeon for further management
Health Tips
Avoid nonveg, maida food, outside food.
High fibre diet daily.
Drink more water