My friend said I'm not really bi-racial, but I am. What the hell?

My mom is Jamaican and my dad is White, originally from London, he moved to America after college. Anyway, so my friend says that Jamaicans are mixed with other stuff, so they are not exclusively Black. Like she said they have Indian, Chinese, and White ancestry as well. All I know is that my mom looks Black, so therefore I am half Black right? She's telling me that I'm not really bi-racial, and it bothers me because it's who I am. I identify as bi-racial, I love both sides, and when someone tells me I'm not bi-racial, it's like a slap in the face. Idk, maybe I'm just being over-dramatic, what do you think? Am I bi-racial or not?!