[Belegorn]

I don't know about the creature in the water being the Balrog. It had at least 20 tentacles. That does not sound like a Balrog to me, and I do not think the Balrog would attack from a point of weakness. When he fought Gandalf the pool under Moria put out his fires. Although those were extremely cold waters. I think the Balrog must have been very cautious after his peers were manhandled in the War of Wrath. I have no idea why he suddenly decided to show himself. Being a resident of Thangorodrim I do not think Dwarves working with metals would bother him much. Melkor always had the smithies going, beating the metals, creating machines, et cetera. Perhaps it was the Gandlaf/Ring combo, but I do not quite think so. Was Gandalf disturbed by the presence of the Balrog? I do not recall. Perhaps if his hair was on end, maybe the Balrog himself felt it, not quite sure why his skin was tingling. I'd think he'd want to stay put if he were still fearing for his life, although they were fighters so maybe he had screwed up his courage after 2 Ages of stealth.