Hello, I have gone through your query and understand your query. You have red blood cells in your semen. Even the presence of single red blood cell is abnormal in semen examiantion. This could be due to injury to urethra during masturbation. But also we have to think of other causes like infection or urethral calculi. Calculi may injured the urethra and the blood from injury may mixed up with semen. This need further investigation to find out the exact cause. Some test like complete blood count, urine for culture sensitivity, USG-KUB (ultrasound of the kidney-ureter-bladder region). These tests need to be done to find out the cause so that appropriate treatment can be started. Hope this helps. Please write back for further queries. Wishing you good health.