There is no clear way to know exactly how many weeks you ae pregnant since there is no clear way to figure out when exactly ovulated and when conception happened. Most doctors and health professionals use the first day of your menstrual cycle to figure how many weeks pregnant you are. So technically if you calculate based on last menstrual cycle you are two weeks ahead in your preganancy than calculated based on your conception and the date of last menstrual cycyle is considered as the first day of your pregnancy.
This would be your ovulation period. During the next 12- 24 hours your egg is set to fertilize, you would be able to confirm this in a weeks time.
Food & Nutrition
Diet is perhaps, the most significant aspect of pregnancy and you ought to eat nutrious food. It is time you start considering folic acid supplements as it's deficiency causes neural tube defect in babies.
Fitness & Exercise
This happens to be a great time to get involved in some sort of physical activity such as walking or swimming. Physical activity is pivotal in imparting endurance and flexibility in the body, essential during pregnancy. Yoga is another example of something you could take on.