Your problem could just be because the faucet is new. If you were used to a full flow from the faucet, then the Government mandated low flow requirements could make you think you have a bad faucet. But if it is a wide spread faucet, then the hoses between the valves and the spout could be kinked and not letting water through.
check the aerator. sometimes the faucet installer doesnt know enough to remove this before opening the faucet for the 1st time. It could just be a simple clogged aerator OR the shut off valves are not completly open