Suffrage is the right to vote in public elections. Universal suffrage means everyone gets to vote, as opposed to only men or property holders. Suffrage has nothing to do with "suffering" — unless the wrong person is elected.
If you want to vote before you’re 18, fight for youth suffrage and get the law changed. In the meantime, once you turn 18, go vote! Kids grow up, of course, but it has been much harder for others to get the right to vote. For example, after trying for about a hundred years, American women were granted suffrage and voted for the first time in 1920. Think about that next time you’re tempted to stay home on election day.