When you're a fast walker, stuck behind slow walkers.

Why is it so awkward? Walking to work today, some bloke in front of me walking slow and me walking at my normal fast pace. Started catching up to him so he kept looking over his shoulder, making me feel even more awkward, like he though I was going to mug him.

Eventually he stops and lets me past, so I awkwardly say "Thank you" but then I had to continue to walk faster like an absolute maniac just so he knew I wasn't going to mug him.