I keep getting a dull ache that feels like its deep in my stomach it's very uncomfortable when I have it and lying down is the only thing that helps.

Worrisome. It's hard to know what exactly the cause is, but what you describe certainly warrants further evaluation including a physical exam, and probably an endoscopy to examine the inner lining of the stomach. These tests are important in checking to make sure you don't have an ulcer or a stomach mass.