Hi,
How are you? This could be due to presence of blood in the semen or hematospermia. This is an uncommon condition and may be caused by many conditions affecting the male genitourinary system. This include any of the following: infection; inflammation; benign or malignant tumors of the prostate, bladder, testes, or seminal vesicles; calculi; polyps in the urethra;ejaculation-duct obstructions; and cysts, hemorrhage, or other abnormalities in the seminal vesicles. Check with your doctor for proper evaluation. Take care and do keep us posted.
I'm no professional But I'd be talking to the doc quick. Maybe even a prostate exam. I hope It turns out well for u.