That's
How I Spent My Summer Vacation by C. Leuch. I just GE'd the newest story in that series a few weeks ago.
Next quote:
Oh no. She'd recognized him. His wild dreams of playing the anonymous hero, finally able to use his powers in the open, had been dashed at his feet. "Better explain yourself
quickly, Kent..." he thought to himself. "Well, I, uhm... that is...." Clark stammered, confused and off-balance, frantically trying to come up with a reasonable explanation.