What were Patrick Henry's concerns in his speech before the Virginia Ratifying Convention?

In the simplest terms, Patrick Henry thought it was crazy for the United States to put themselves under the rule of a consolidated government. What had the Revolutionary War been fought over if not freedom from unfair tax policies and the oppressive British rule under the tyrant King George? Henry took issue with the idea of electing a president for fear of America appointing a despot of its own.
As an Anti-Federalist, Henry opposed big government and favored states' rights. At the time of Henry's speech, many Americans' strongest allegiance was to their state and not to America, which was still in its infancy. Henry was a five-term governor of Virginia, and as such, he was very concerned about the economic future of Virginia and the entire South. Henry simply did not trust the North to keep the South's best interests in mind, and he felt like he had been burned before. For example, it was Henry's belief that Congress failed to send enough troops to the Ohio River Valley to protect Virginia settlers there. He was also a staunch opponent of the Jay-Gardoqui Treaty, which would have sold the navigation rights to the Mississippi River to Spain for 25 long years.
Henry was a fierce protector of personal freedoms, as well. He wanted the Constitution to include a bill of rights that would safeguard individual rights. Liberty, Henry believed, should be America's highest and most shielded priority. He wanted the Constitution to set limits on the government's power and avoid placing the future of many in the hands of few. In particular, Henry wanted to strip the government of its power to establish and collect taxes. He and his fellow Anti-Federalists feared that if the government was allowed to tax and spend at will, they would quickly spiral out of control, racking up dangerous levels of debt.
Ultimately, Henry was defeated. Virginia approved the Constitution by a vote of 89-79, but Henry never wavered in his belief that the Constitution undermined the very spirit of the American Revolution.
http://press-pubs.uchicago.edu/founders/documents/v1ch8s38.html