My daughter got a C in math freshman year of high school, and a B in bio.
She is now a rising junior at UC Berkeley, where she is a Regents’ scholar (awarded to the top 1-2% of all applicants).
So I do not think this B will not make or break your application.
(Edited to add: For her, these freshman year grades were a wake up call. Like you, she was disappointed in herself. But instead of giving in to despair, she stepped up, got to work, and improved her grades in subsequent classes. If you are determined, you can do the same. )