What does it mean if you can feel pressure under your ride side of ribs?

Lots of things maybe: May be musculoskeletal;intestinal gas; pulmonary, liver issues, gallbladder issues, colonic issues, duodenal, stomach issues, uncommonly referred pain from pelvic (gyn) organs. Depends on type of pain, duration, associated symptoms, severity, age, sex, meds, other conditions. See your doc.

Many possible things: This complaint can come from a number of different things. It depends on the character of the symptom particularly when it occurs (rest, exertion, deep breaths). It may be harmless, like a strained muscle or cramp, or represent something more serious, like coronary artery disease. It depends on your particular risk factors, which include things iike age, high blood pressure, diabetes, etc.