Welcome to the forum. The symptoms of nausea
that you are experiencing are natural and normal. It is known as morning sickness
( begins from 6th week and gradually disappears by 12th week ). It is nice to know that you have gained weight. You should stay in contact with your gynecologist and have monthly check-ups. Gain in weight ( atleast 1 kg ) should be there every month.
You should take the dietary supplements and tabs that your doctor gives. ( follow the doses exactly as prescribed ). Eat nutritious food. Take fruits and berries, high protein diet.
The burning discomfort that you have in your chest and stomach is because of gastritis
. It will get fine with antacids ( consult your treating doctor). To avoid formation of gases take food 3 -4 times a day. Maintain a proper timing of the food intake.
Get all investigations done. Have a nice day.