The condition pharyngitis is essentially another name for a sore throat which is the less severe condition even though sore throats or pharyngitis is still pretty bad and make it hard to swallow or eat anything.
But the Laryngitis is the worse of the two because it can sometimes last longer than a week and there's not too much you can do for the Laryngitis unless it's caused by bacteria.
Pharyngitis is inflammation of your pharynx which is basically a sore throat while Laryngitis is the inflammation of the larynx which is your voice box that allows you to speak.
The Laryngitis is usually caused by either a bacterial or viral infection and if it's caused by a bacterial infection then antibiotics can help get rid of the Laryngitis.