Ginkgo biloba

I am 33 and just started taking Ginkgo biloba to kickstart my brain - it seems to be doing just the opposite - I feel spacey! Why is this? Are there some forms that are better than others? I thought the "natural" way was the best way - I don't like caffeine to kickstart me - it gives me the nervous jitters!
For your information, I also take a multivitamin and mineral supplement, Super B Complex, and a calcium, magnesium, and zinc supplement.

Varro Tyler, in "Herbs of Choice" (Pharmaceutical Products Press, 10 Alice Street, Birmingham, NY, 13904-1580, U.S.A.) lists infrequent side effects as headache, allergic skin reactions and gastrointestinal disturbances. However, individuals can respond differently to any herb or medication.
The recommended dosage, three times daily is:
* Tea: 1 teaspoon dried leaves, gently simmered in 1 cup of boiling water for 5 minutes
* Tincture: 2 ml of a strong tincture, made with 2 parts herb to 1 part alcohol
* Capsule: 250 mg of Ginkgo or 40mg of a standardized extract
You could try a smaller dose of Ginkgo or use different herbs. A good tea combination to start the day, or to revive you during the day is a combination of: Rosemary, Gotu Kola and Ginger, which are all stimulating and improve circulation, including circulation to the brain Orange peel, which feeds the blood vessels Hibiscus, Cardomom and/or Spearmint to taste. These are warming and have digestive properties.
You may want to try a small amount of one of the stimulating herbs to see how it affects you.