I've suffered being bullied in the past by kids that are quite frankly younger that me.
Today, I was the only one running the 100 m dash. As I was running, the visiting team was shouting at me rudely and it brought up bad memories from my past. I'm frankly really upset now. How does anyone cope with this situation?

My only suggestion is to put the pain into something productive. Run harder? Maybe draw or wrrite or something. Sorry I can't be of more help.

>>1 like >>2 said, hobbies help, especially when you can healthily release your emotions through them, like for myself I sing and write and it helps a ton.
Sometimes old memories surface and it hurts but you need to remember that you're moving on and that you're a stronger person now and you can't let the past get to you.