My mom is insane?

Today, I was walking home but then I decided I wanted a Mountain Dew and we never have that so I went and bought a Mountain Dew. I got home and my mom freaked. She started yelling about how I crossed 6 lanes of traffic (3 lanes on each side of the road) and how I was alone. I am 15. Does she have a reason to freak out? I am pretty safe. I use the crosswalks and stuff like that.