I have gone through the query and understood your concern. Pregnancy
is not possible since you have had a normal natural period as per schedule. This recent change in the menstrual pattern associated with symptoms of nausea
and pain needs to be explored. Prostaglandin
release prior to the onset of a period can give rise to the symptoms you are experiencing. Hormone imbalances can crop up due to sudden weight changes, stress
, infections, cysts in the ovaries and certain medications. Endometriosis
is another cause for pain. You need a clinical review to detect the cause and plan proper treatment. Please maintain a healthy weight and a healthy diet. Take care.