The only military record that I have found is in The book compiled and written by William Stryker entitled "The Official Register of the Officers and Men of New Jersey in the Revolutionary War," published in Trenton, NJ in 1872, page 628. That is the only record I have found that refers to a Joseph Hewlingsthat served from Burlington County, NJ.
The Continental Army was an army formed after the outbreak of the American Revolutionary War and was established by a resolutions of the Contintial Congress on 10 May 1775.It was created to coordinate the military efforts of the Thirteen Colonies in their revolt against Great Britain. The Continental Army was supplemented by local militias and other troops that remained under control of the individual states.
So the term Continental Militia was used by local's in reference to those militias that joined the Continental Army as opposed to those Militias that were formed at different time periods and those formed specifically for protection against Indians.