No se hubiera / te hubieras molestado.
You shouldn't have (bothered).
Gracias. No se /te moleste/s.
Thank you. Don't trouble yourself (Don't bother).
No es necesario, gracias.
It's not necessary, thank you.
No se /te preocupe/s (por eso).
Don't worry (about that).
No ha/s debido hacer eso.
You shouldn't have done that.