I've taken chlorella in the past and didn't have any issues that I could remember. What are the symptoms people might get from it's use?

This is the day after removing my amalgam filling. What supplements should I being taking daily and for how long? I am currently on MCP, one tablet of charchoal, some chlorella and 5,000MG of Vitamin C daily. Will try the Algin this week and see how my body reacts. The first time I took it my lower back was hurting. Not sure if the Algin was the reason or something else. Thanks Guys!