What Causes Passage Of A Parasite In Urine?

I had just gone to the bathroom after lying in bed for thirty minutes, and showering twenty minutes prior to getting in to bed, when I noticed what appeared to be a bug swimming, just the size of a needle head, that wasn't there before. Upon closer examination when I removed said bug from the toilet bowl and placed it in a small, clear plastic container, it appeared to have a transparent body and dark brown inner workings. It looks to have six legs with two antennae, and a tail half the size of the body that comes to a transparent sharp point. Is there a parasite that lives inside the urethra, bladder, or urinary tract that matches this description?