Is my mom wrong for reacting like this?

This morning I had lost my house keys. I searched for them in my backpack up until my mom was at the drop off at school. She stopped the car, pointed to my bookbag and said “Dump everything out” in a rude and snobby tone. I did and of course they weren’t there. I figured they were in my room so I didn’t think much of it and it’d be almost too easy to go make another one at walmart for a low price if they didn’t turn up so I wasn’t too concerned, since I’d obviously pay for them. She freaked out screaming “YESTERDAY YOU LOST YER BACKPACK NOW YOU LOST YER KEYS! GET OUT!” (I quite obviously didn’t lose my backpack since I was rummaging through it, but yesterday my friend had my backpack and I couldn’t find her, that’s all that happened). So I get out of the car and when she sees my back up pair of flip flops I wear to walk home, that I was about to grab she throws them out the car and speeds off before I barely even close the door. Was this an immature reaction to a simple pair of misplaced keys?