I had iffy veins too but those experienced nurses usually find one and are very cautious giving it to you, especially the 1st dose. I didn't have my port in until my 4th dose, but they managed to find a vein 1st go each time. ..only one, but they cherished it. (And they obviously found one for your surgery. ..so they will find one )
I am es+pr-Her2+ and my cancer was found by myself 5 weeks after a clear mammogram. I was fortunate it was close to the surface and easily detected.
It certainly is a frightening time at the beginning with so much happening and so many unknowns but it will soon enough feel like a routine you will settle into.
We are here to listen and I hope 1st chemo goes well. Kath x