school dress codes are a joke

I was walking down the hall with two plants in my hand because I was told to water them. Apparently like half an inch of my stomach was showing and this teacher flipped. She walked by me and went "what the heck is up with that" I was not aware she was even talking to me because she was talking to a different student like seconds before. So I kept walking and she kept walking and when I was almost in my class she said "you're out of dress code." And I said okay and she was like "DID YOU HEAR ME. ZIP UP YOUR JACKET NOW" and then she said did you hear me like 4 more times and I was like yes then walked into my class. And like she expected me to just drop the plants in the hall to zip up a jacket like girl. I just walked into the office and no one cared about my shirt. I understand that i was out of dresscode but I didn't realize that gives the right to teachers to be dicks. And honestly I feel like there are worse things than an inch of my stomach showing. Like there are girls at my school with their boobs and butts out of their shirts and pants. Which is fine if that's what they like but why am I getting in trouble for a small piece of non sexual skin? I just think school dresscode is so stupid