Last minute complications - protein in urine test

I am having my surgery on monday, or maybe.

My blood test revealed low Protein (total and albumine)just under the normal rate, just barely, but now I need to do a urine test and I just know that it will be positive for protein.

I have smelled it and I can smell that slight buttery scent that would indicate protein in them.

Now I have asked the nurse and she seems to think that if I do have some protein in my urine, the surgery will be cancelled. I am so disheartened. The next slot for an operation will a long time from now.

I am wondering if anyone had such a thing happen to them. Is impaired (of it turns out to be that) kidney function a contra indication to this surgery (sleeve)?

Thanks