Possibly sexual harassment? TW

This happened to me when I was 16 years old and in high school, I’m now a sophomore in college. I just wanted to get this off my chest because I haven’t told anyone. One day I was sitting in the car waiting for my mom to come out of the grocery store and I had my windows rolled down half way so I could get fresh air. A guy in a car pulled up next to our stall and he rolled his window down all the way and I’m pretty sure he noticed me, and he unzipped his pants and started masturbating. I remember actually hearing his hand against his skin and i didn’t have anything like earphones that I could use to block out the noise and I didn’t have the car keys. I didn’t know what to do and I was so scared to say anything. I didn’t tell my mom because I felt so embarrassed like it was my fault like I did something wrong. It lasted around 15 minutes. I feel so gross thinking about it even though I did nothing wrong. I just turned the other way and avoided looking in his direction. I’m not sure if this qualifies as sexual harassment but I felt very violated.