I have a black spot on the side of my big toe nail. I got a nail fungus a few years ago at a salon.... Tried topical and even pills... Now this spot?

Differential . Diagnosis would include fungus, dried blood or worse case scenerio something serious like melanoma. It is more likely on of the first two but since melanoma is dangerous warrants it be checked out.
Black spot. It may well be fungus again. See your podiatrist for an evaluation and treatment.