Ruby, you CAN quote from lyrics on Medium: Broadly speaking, under U.S. law, it depends on the proportion of the lyrics you use and other factors (such as whether they're still under copyright).

You couldn't quote all of the lyrics for, say, Taylor Swift's "Reputation," but you might be able to quote a line from it if do it accurately, not misrepresenting it.

I'm not a lawyer and can't say whether what you used was OK. But people do quote lyrics Medium without incident.