I have a friend who puts an exclamation mark at the end of every single sentence in her emails.
A feeling where you sigh is one in which you're surprised by something, and can't believe it, so you sigh. Ugh, *sigh*. What token represents this in writing? An exclamation mark!!!!
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.