I think i may have bacterial vaginosis how do i know and how did i get it?

I think i might have BV i have a reoccurring oder and allot of discharge its extremely embarring also its been stinging when i go to the bathroom because ive been scratching so much that i cut myself. I know i didn't get it from not washing because ive been taking 4 showers a day now and its still the same so if this is what i have how did i even get it and how can i stop it?