Dread block around art commissions

I have two art commissions that are due tomorrow.

I am feeling a heap of terrible about them.
I can’t believe I waited this long.
I think I’ve got a brilliant concept for them but they are turning out terribly thus far.

I just feel such a huge block of terrible that I want to curl up and cry and I go to work on them but feel terrible.

I am just feeling so terrible – and I need to finish them.

Is the answer just to feel the discomfort of terrible and finish them anyway?