Some white person just called me, a black girl the n word i reported but what else should i do? that is racism and offensive!

No, white girl should call you the n word. It's not a right word?

Also, why did she call you the n word?

Because, this happen to me once.

Some guy, call me the n word for no reason?

And, like:

He doesn't even know what the n word means.

i'm not sure i completely understand your question, but i will do my best.

i think the answer you are looking for is sequence. (see below)

a repeated melodic fragment would be best defined as repetition, while repeated chords (different or the same) could be a chord progression. however, you then mentioned the chord and melodic fragment beginning on higher or lower pitches, in that case, the answer could be best defined as a sequence. the definition of a sequence is as follows: "the restatement of a motif or longer melodic (or harmonic) passage at a higher or lower pitch in the same voice."

let me know if this !