I think this poem is okay, but doesn't have the usual metaphors and descriptions that I know you sometimes have. I think you could make this better by adding in some more detail.

Show us more about the violence? Like who and what is happening?
Show us how you are scared to sleep?

Also, in your last lines, you could change the first "that" to "it" to stop the repeated "that"

I like the title choice - I think it related to the point where you would not even hesitate about the knife if you had to in self defence:protection.