Abbie, Chloe, and Xander are playing a dice game. The game consists of ten rounds. In each round, each person takes a turn rolling two dice and earns or loses points based on what they role. Points are awarded according to the following table: Roll Points
Same number on both dice +3
Different numbers, with an even sum +1
An odd sum -2
At the end of ten rounds, the person with the highest number of points wins.

In the first five rounds, Abbie got four odd sums and one pair of threes. How many points does she need to have an exact score of zero? What is the least number of rounds it will take her to have an exact score of zero? Explain your reasoning using complete sentences.