I'm not that familiar with the phrase "vamos como un péndulo," but the first part I do know. What is the context? Possible translations: We've been bouncing back and forth for I don't even know how long. We have been going from place to place for I don't even know how many days. Hace unos dias = A few days ago Hace no sé cuantos días = I don't even know how many days ago

No estoy segura , pero me suena a "Hace días que le estamos dando vueltas al mismo tema/problema ..." Espero te ayude.

It's a "popular saying" from some Spanish-speaking people, "hace no sé cuantos días" = "it's been several days" "que vamos como un pêndulo" "we going like a pendulum", means he's already lost count of how many days he's coming and going, he says this when he can't get something he wants (money, job, home, etc).

Thank you.

I don't know how many days we've been going like....