Semen character can differ from person to person. Sending a sample off for analysis can be considered if this continues to be a concern.
Infection can change the character of the urine or semen. Again, a urinalysis and culture can be helpful in the diagnosis.
If there is blood in the semen, the prostate should be examined and imaged for possible mass or infection.
These options can be discussed with your urologist.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.