Writhing leeches

Pick a point with in 50 ft Of your self, from that point a 10 ft radius of leeches appear. Any creature that is in or enters the perimeter has to make a dexterity saving throw equal to the spell casters spell save DC either when their turn starts or when they enter the perimeter. on a successful save nothing happens on a failed save a leech attaches to the creature, the creature takes 1D4 piercing damage for each attached leech every round at the end of the creature's turn, The creature will take damage from the leeches until the spell ends or the creature removes them, a creature can use an action to remove up to 2 leeches.