Most Common reason in early pregnancy is acidity & stress , so she should avoid spicy & oily food. Should take non-spicy , easily digestible food at regular intervals. She should not be empty stomach for more than 3hrs. For acidity & gas(abdominal distention) Syr. Gelusil MPS 2 tsp BD. If required can take  tab Paracetamol500 with Gelusil Syr.

She can take paracetamol for headache but the reason for the headache should be evaluated

Tab paracetamol 500mg is safe during pregnancy