Pain and burning sensation in stomach!

It all started with a mild pain in lower left side of stomach and gas over there, I am having gas and pain since 4 days after i took medicine i got some relief but the gas is still there. I feel like someone is knotting my stomach and feel discomfort in stomach!! After i eat something it pains in lower left side, if i take water it pains there but the pain is less since after taking medicine. Now i also feel burning sensation in chest and food pipe after eating food and on some occasions too! The gas kinds of revolves around in stomach,sometimes i feel to vomit but i cannot. My stools were normal this morning but there was a feeling that i hadn't finished and pain was there in stomach! My chest also burns like under the heart area where ribs ends!! Please suggest something!!