How long will it take me to look thin, slightly muscular (for a girl), and lean if I am training for cross?

country in high school (so I will be running about 3 miles 4 days a week), if I cut the sugar/sweets/chocolate/etc, and I cut refined white flour products like biscuits and white bread buns from my diet? I probably eat about 1300 calories a day of wholesome foods, maybe having 1500 on Saturday for a splurge. I am trying to eat lots of meat, such as eggs, fish, chicken, venison, and beef because I heard protein contributes to muscle building? Oh, and I do have a gym class too for an hour 4 days a week.