Interesting! WHen I was eight years old, I was also “bullied by boys” at school, and also had “strong anxiety and stomach ache” as a result.
This usually tended to occur on exam days.
When my daughter was being bullied and jumped from behind by 7 and 8 yr old boys... I enrolled her in Judo class. All it took was throwing them to the ground once. Of course the teachers put HER on the yellow line during recess! I told her if she had to stand on that line every day, no matter, she had to defend herself.