My sister had it around the same time, when she was in elementary school. She ended up hospitalized and almost died from it. People need to get vaccinated as soon as they can get it, however bad you think it is, no matter how high your pain tolerance is, your nerves burning like that is worse.

I got it when I was in middle school, it was one of the most painful experiences in my life. Nothing could lessen or get rid of the pain, just the constant sensation of direct mains current plus it feeling like my skin was literally on fire over a quarter of my body.