actually got treated very well at the US Embassy in Bangkok and then very offhandedly at immigration in New York. One of the snottiest I've come across was at the island of St Helena, jumped up prycke. He felt it was part of the "job" to be awkward. I doubt if he did a 40 hour year.
which visa are you renewing.? A visa basically permits you to enter a country so once you have entered it is used. As you are already in the country you cannot be issued with another one.
You do not say which visa you have, possibly you are confusing an extension of permssion to stay for a visa.