Normally, parasites are in feces.
A urologist is a doctor that specializes in the urinary tract (kidneys and bladder) I don't see this as urgent as you do not have any symptoms such a pain or blood in your urine.
I would monitor the situation, perhaps get a large disposable cup and urinate in it a few times to see if you see this again. If so, bring it to the doctor.
If you give me your zipcode, I can give you a list of urologists.
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