Good call with the vet visit--in the meantime I would keep her on paper towels so you can monitor for signs of discharge/residue, and prevent anything further from irritating the area until it gets fixed. I've heard impacted bowel is typically very hard; if the area is squishy it's possible she might be gravid. My BP female became gravid even though she hadn't mated with another snake and she bulged quite a bit like that near the tail when she got closer to delivery. Good luck.