At first, the pain is blinding. All you feel is the pain.
If you can get the bleeding stopped, eventually the pain subsides, but things aren't ever really "normal" again. You find a new normal. You even learn how to do almost everything in your daily life with one arm. You adapt, and you may even thrive.
But every so often, something happens and you're genuinely stumped how you'll handle it with one arm. It reminds you of the loss, and in that moment, the frustration and the loss and even the pain comes back.
You'll cope with it, like you coped with learning everything else you needed to learn right after you lost your arm, but it never goes all the way away. You just get better at living with it.