Ok, I can totally sympathize with how you are feeling right now. You must be frightened and worried. My first thoughts were the same as the dentist mentioned; that it is solid mercury you have swallowed and not vapour so this is very good.

I don't use Algin so I'm not familiar with it. I would recommend taking lots of bran (the one with the highest fiber content available) to get the bowels moving FAST, and eat food which is alkaline. This is because acid can tear on the amalgam in your colon. This means vegetables and fruit for a few days and no protein. I would also avoid starch food as these slow down bowel movements, meaning no potatoes or grain foods for a few days.

Best of luck