Thanks for posting your query.
Diabetes is due to progressive loss or destruction of beta cells in endocrinal part of pancreas.
Diabetes is a multi organ disease with involvement of almost all organs of body due to its complications.
Blood sugar both fasting and postprandial must be in controlled range.
With the available described symptoms, there appears to be high possibility of uncontrolled diabetes
Nausea and giddiness could be due to gastritis, side effect of metformin, gastroenteritis
and diabetic gastroparesis
You should consult with with internal medicine specialist/ endocrinologist
and should go for thorough check up.
You should also go for blood sugar fasting and postprandial, glycosylated hemoglobin, lipid profile
, renal function test and endoscopy.
Treatment depends on exact diagnosis.
Meanwhile, you should take proton pump inhibitors and prokinetics.
You should take proper treatment for control of blood sugar.
Dr. Mayank Bhargava