Hi and welcome to Healthcaremagic. Thank you for your query. I understand your concerns and I will try to help you as much as I can. In young people some serious issues arent to be considered and this is probably blood as a consequnece of hart stool and straining. Constipation may be caused by several issues, however you should try first with changing lifestyle and dietary habits. You need to increase fiber intake. Good fiber sources include bran and other whole grains found in cereals, breads, and brown rice, vegetables such as brussels sprouts, carrots, and asparagus, Fresh fruits, or dried fruits such as raisins, apricots, and prunes Beans. Also, you should exercise regularly. Second, you may at times need to try a laxative such as Fleet Phospho-Soda, Milk of Magnesia, or glycerin suppositories. If there wont be improvement on these measures, you should consider doing diagnostic tests such as colonoscopy, anal sphincter manometry and food allergy testing. In some cases it may be also sign of tumors so it should be ruled out if symptoms persist. I hope I have answered you query. If you have any further questions you can contact us in every time. Kindly regards. Wish you a good health.