Bedsores develop in stages, showing how the damage to the skin and tissue progresses. Stage 1: The skin looks red or darker than usual and may feel warm or firm. The area might be painful, itchy, or sensitive, but the skin is not broken. Stage 2: The outer layer of skin is damaged, leading to an open sore or blister. The wound may look like a scrape or shallow crater. The area can be red, swollen, and painful. Stage 3: The sore gets deeper, damaging the tissue under the skin. It may look like a deep crater and could show fat beneath the skin. Signs of infection, like redness, warmth, or pus, might appear. Stage 4: This is the most severe stage. The sore is very deep, affecting muscles, bones, or tendons. The area is likely infected and can cause severe pain.