Pensarse

Pensarse
 

Lyrics from Me voy de casa (a Mecano song):

Al salir de casa dio un portazo tremendo
Todos se quedaron sin la respiración
Ellos se pensaron, volverá al momento
Y él se fue corriendo y cantando esta canción

Is “se” pensaron correct here?
Does it mean they thought “to”’ themselves?

Many thanks.

Just taking a shot in the dark here, but could it be an informal/non-standard way of saying "They thought to themselves" or "They thought among themselves"?

I'll have to let our members from Spain correct me, but as I've seen it used, "pensarse" in Spain is used in the sense of assuming something.


- Se pensó que era un comunista buscando follón.
(Another Mecano verse) He thought that I was a communist wanting to get in trouble.


- ¿Quiénes se piensan que son?
Who do they think they are?


- Si te piensas que voy a tener al perro en mi casa, estás muy equivocado.
If you expect me to keep the dog in my house, you're very wrong.