Oh, I feel that! I once panicked running for a train, and suddenly I was back on that solo trip where I got totally lost and my chest felt like it was squeezing me. What helped me was slowing down my steps, feeling my feet on the ground, and just noticing my surroundings instead of racing thoughts. Also, I found this really practical guide with ways to calm anxiety on the spot: how to calm anxiety before a stressful event . Small things really reset your head!