I'm no expert on this, but when entering a country, your rights are quite different than they are once you've been admitted into the country. For example, the right to unreasonable search and seizure does not exist until you have been admitted - border officers have the right to search your property even without reasonable cause.
I'm guessing at a certain point you would have the legal right to counsel but it may not be immediate. It may depend on what the officers intend of you.