dnd 5e – When casting Infestation as an opportunity attack with the War Caster feat, how does the forced movement affect the targets turn?

With the War Caster feat, you are allowed to cast a spell as a reaction when a target provokes an opportunity attack. The infestation cantrip states that the creature

moves 5 feet in a random direction if it can move and its speed is at
least 5 feet.

Does that creature then end its turn, or does the creature simply move 5 in a random direction and then continues its turn as normal?

The description also states:

if the direction rolled is blocked, the target doesn’t move.

Does this mean that in this specific scenario the target loses its movement, or is it simply referring to the 5 feet forced by the spell itself?