Why did he say Cherpah broke his heart?
Malbim: The heart is the source of life; it is broken.
What is "va'Anushah"?
Rashi: I will be mortally ill, like "Ki Anushah Makoseha" (Michah 1:9). A root that begins with Aleph, the Aleph can also indicate first person 1 , like "va'Ohev Es Yakov" (Mal'achi 1:2). "Asof Osef" (Tzefanyah 1:2) is like E'esof.
Malbim: It is a mortal blow, for it reached my heart.
Radak It should say ve'E'enushah; the Aleph of the root is omitted, and the Aleph of the conjugation is written. The Cholem (in Enoshah) is changed to a Shuruk, like "Lo Sa'avuri mi'Zeh" (Rus 2:8), "Yishputu Hem" (Shemos 18:26).
What is "Lanud"?
Rashi: Lovers should come to lament over me and console me.
Malbim: The verse depicts as if he died, and wants people to console and lament over him like they do over a Mes, but no one laments or consoles over him.
Why is there a Patach under the Lamed in "vela'Menachamim"?
Radak: This is in place of Hei ha'Yedi'ah (to identify), the known consolers, i.e. those who appeared to me like lovers.