[noun] + に過ぎない [verb (plain)] + に過ぎない
に過ぎない means "is no more than", "is merely". It follows a noun, or the plain form of a verb, and makes what comes before it sound small or unimportant. The polite form is にすぎません過ぎません.
Said about yourself, it is modest: you did nothing special.
に過ぎない belongs to writing, news, essays and formal speech. In conversation, だけだ or ただの + noun says the same thing.