Sharp abdominal pain on LEFT side, BELCHING

Hello,

For the past 3 days, I have been experiencing the following symptoms:

- Sharp pains in my left upper abdominal quadrant. I experience these pains at different locations at different times (usually 24 hours apart); most common pains are located: in the umbilical region, left lumbar region, and left hypochondriac region

- Frequent belching

- Loss of appetite

- Left abdominal region feels much harder than my right side

- Pain ranges from short, minor pangs, to prolonged pain

I just went for an ultrasound earlier today, and noticed a presence of something on one side of my abdomen. Does anyone know what it could be?

Thanks