WILLIAMSBURG-It wasn't much of a winning streak anyway. After sweeping three games against Bucknell over the weekend, the Virginia baseball team's attempt to continue its victorious ways fell short yesterday as the Cavaliers' fielding and pitching woes resurfaced in a 9-3 loss at William & Mary. The Cavs (3-7-1) committed three errors in a three-run Tribe fifth, meaning only four of the seven runs allowed by junior lefthander Brandon Creswell were earned. William & Mary 9, Virginia 3 Cavalier Daily Box Score   "We were pretty embarrassed that we didn't play the defense that we wanted to play and we probably didn't throw the ball as well as we wanted to either," Virginia Coach Dennis Womack said. In the bottom of the fifth, with the Tribe (10-2) holding a slim 2-1 margin, the Virginia defense handed William & Mary the runs that would win the game. With one out, Tribe third baseman Stephen Booker reached on an error by Cav second baseman Dan Street.