Just a quick question on circumcision ...?

The veins are only there to provide blood to the foreskin. Once the foreskin is removed by circumcision they are not required. During the circumcision any veins that serve the removed foreskin are cut through and sealed to stop them bleeding. You have many more veins to serve the rest of your penis, which will not be affected. Your body will also build whatever blood supply system is required after the cut settles down.