Tsunami alter at the south of chile and argentina

i just heard at the radio that there is a alert at the south of chile and argentina coss of a (dont know how it say that earthquake under water) near japan.
i really scared. i have a lot of friends and families friends living at at the south.
and the worst thing is that this alarm it was published a few hours ago and here is night. i dont want to wake up and see the worst.