Try to avoid gassy or spicy foods and eating late at night. This tends to last for only the first trimester and usually in the morning when you get up. However, that being said, nausea can happen at any time of the day and can last throughout the whole pregnancy. Try setting your alarm a few minutes early and remain still in bed for a few minutes before getting up. Some say soda crackers before rising can help.
Breasts can become very sensitive in pregnancy.
I would sleep almost 12 hours a night easily during my first trimester. Get as much rest as you can, your body will let you know what rest it needs. Hormonal changes in your body contribute greatly to exhaustion. If this is not your first child, consider having someone look after your other children for a few hours so you can catch a much needed nap. Sometimes low blood sugar can cause dizziness or even the growing uterus can be placing pressure on the arteries.