Change your hairstyle. Go to a salon and get a facial or manicure. Spend time on you. Eat breakfast every day - it's a good start. Keep plenty of fresh fruit on hand.
Fruit is a natural energy booster.
Buy a book about postpartum depression and read it. There are many women out there who suffer from this disease every day. Find the resources to help yourself or ask someone you are close with to help you. Make meals ahead of time and freeze them for the days you just can't get it together. You will have something to throw in the oven for dinner.