No need to worry at all about only 1-2 bines coming out so far. If this is your first year with the hops, you may only get a few actually coming out of the ground. They will not branch off of each other, they only come from the rhizome in the ground. You'll probably see more bines coming out as the season progresses. I would recommend cutting back all but 2-3 of those anyways to ensure proper root growth and give all the nutrients to the bines you are letting grow.
Next year, you'll see many more bines coming out of the surface. Hopefully you'll get some type of harvest this year from your first year crop. Best of luck!