Thanks for choosing health care magic for posting your query.
Although urine and semen share a common path to some extent , rest of the path is different. The fact that there is blood in semen and not in urine suggests that the injury
or lesion is well before the place where the semen tract connects with the urine tract.
I understand that its only last 4-5 days that you are having a problem and at this stage you need not worry. There could be some mild trauma which settles down by its own and may bleed during healing stages.
If the problem persists then you should take a urine routine microscopy, semen microscopy, USG abodomen and pelvis, bleeding time
and clotting time and if required a urethroscopy.
This will help in dealing with the things properly.
Hope I am able to answer your concerns.
If you have any further query, I would be glad to help you.
In future if you wish to contact me directly, you can use the below mentioned link:
Wish you good health,
Dr. Srikanth Reddy M.D.