No, the work week was never longer than six days. At the end of each lunation, as the month transitions from the old to the new, one of two things happen: 1) either you have a seventh-day Sabbath immediately followed by New Moon; or, 2) you have the seventh-day Sabbath, followed by a work day, followed by New Moon. Anciently, the New Moons were kept as Sabbaths, so there was never more than six work days between worship days.