1)
What is the meaning of "Hiktzarta Yemei Alumav"?
1.
Radak: You shortened the days of his kingship. [Even though Alum means youth,] this is like a person - bodily, his youth is his days of good, and his old age is his bad days - "Ad Asher Lo Yavo'u Yemei ha'Ra'ah" (Koheles 12:1). The days of kingship were short, and the evil days (Galus) were long.
2.
Malbim: [Nebuchadnetzar] slaughtered Tzidkiyah's sons in front of his eyes, and then blinded his eyes. This shamed him, and due to it he died prematurely.
2)
Why does it say "He'etisa Alav Bushah"?
1.
Radak: He is shamed (covered with it) due to the promise that You promised him. The enemies say that he has no more hope.
2.
Malbim: Refer to 89:46:1:2.
