You can check on you tube with Jordon Blake video's ( the Liver Flush man) about fermented urine. He states urine ferments can grow mold. Some persons say to skim it off, but he suggests since it it so readily available to pitch the urine that grows mold.
It is not unusual to get a bit of sediment on the urine, but growth on the top of the urine isn't something you would want to keep. So either skim off the mold, or throw it out and personally, I would throw it out and start again.
Putting a coffee filter on top with a rubber band around the rim.