First of all, you should undergo one blood test
for beta-hcg and TVS scan to confirm pregnancy and gestational period.
Nausea, mild abdominal cramp
, low back pain
, slight spotting are quite common in early week of pregnancy. Stomach ache or upper abdominal pain
may be due to indigestion
problem or acidity. Ranitidine group of drug can give symptomatic relief.
Following test report, you need to consult with gynecologist for suggestive measures. In the mean time, you should take healthy protein rich diet with more vegetables, drink more fluid/ water, avoid long journey/ heavy work, take adequate bed rest, start to take folic acid & vitamin supplements, maintain genital hygiene and do periodic check up.
Be well and good luck.