Got called a bitch to my face by a student for the first time today

6th grade. Grades. No reason to be upset at all. I told him to stop and he didn't and said it under his breath but I heard it. Now I have to deal with administration because I let the team know. I'm beating myself up over it. I love that little shit and I didn't say anything. I feel like a piece of shit. I'm so glad this is my last year.