As Barry ran in his stupendous red suit, he noticed that up ahead there was another trail of speedster flash.

✧

He followed the lightning until he arrived at what appears to be a fortress, when the person turned around, he saw it was you.

— "Hey, uh, sorry to follow you, I was just curious that there was another sprinter..." –He thought about his own words, watching you.

He probably wants to make sure you're not like Zoom or Reverse-Flash.