Am I black?

So this is so weird because I literally just found out about it a few days ago. My mom’s been sick but they couldn’t figure out what’s wrong with her for years until she had some genetic testing done and she is 20% subsaharan African. She confronted my grandmother about it and my grandmother confessed that she’s half black. My great grandfather would cheat on my great grandmother when he was in the military and had love children all over Europe and Asia and to get back at him (my great grandfather was racist and this is before divorce was an option) she would sleep with the black men in town hiring them as “handymen” while he was gone. She got pregnant with my grandma and she was light skinned enough to pass for white as long as she cut her hair short in a pixie cut which she’s had since as long as I can remember so that’s what they did. This was pre civil rights in a southern small town so there was a safety concern for her and my great grandmother and I don’t know if my great grandfather ever even knew or when my grandmother found out the truth but I went and got a DNA test and I’m 12.5 % subsaharan African as well which is crazy to me because I am pretty white and my hair is blonde and I would’ve never believed it if I didn’t have the test results right in front of me. But the question I’m dying to know, does this make me black even though I look white? And What percentage of black is enough to be considered black? Thanks