"It's such a simple thing."
(Quite silly, really. (The word "trivial" comes to mind.))

"It's no big deal."
(Though it didn't seem that way at the time. (I suppose it never was.))

"Let's not make a fuss over it."
(I've already made enough of a fuss for the both of us (but now I'm done.))

"It's alright. Don't mention it."
(No, really. (I'd prefer if you didn't.))

((When) a heavy weight gets lifted(, what does it sound like?)
(and)
(Somewhere in the background, (just barely audible (in order to hear it, you'd have to be really listening.))
applause.))