My last period date is 4th august, on 11 sept i had beta hcg serum test and was negative. i want to know now when i should test again to rule out pregnancy also i'm having no symptoms of pregnancy but feeling dizziness alot. please guide. thankyou?

Dizziness is a symptom of early pregnancy, and also a symptom of anxiety. Were your prop periods regular? Did you have unprotected sexual intercourse 12-14 days prior to the missed period? A missed, late or lighter than usual period is a sign of pregnancy, especially when unprotected coitus has occurred. You would be well-advised to see a board-certified ob-gyn to evaluate the symptoms.

As Dr. Lasnover has noted, dizziness is a symptom of many conditions. It is likely you developed a dysfunction in your hormonal system that causes menstruation. You have had a neg serum. By now, any OTC test should be positive. A visit to your gynecologist can help sort this out. It will probably start back on its own, but your doctor can use medication to help as well.