short answer : it is unlikely to a deep tissue injury detailed answer: ‘deep tissue injury’ is an injury to a patients underlying tissue below the skin’s surface that results from prolonged pressure in an area of the body. Similar to a pressure sore, a deep tissue injury restricts blood flow in the tissue causing the tissue to die. the area may be preceded by tissue that is painful, firm, mushy, boggy, warmer, or cooler as compared to adjacent tissue. DTI many be difficult to detect in individuals with dark skin tones. Evolution may include a thin blister over a dark wound bed. The wound may further evolve and become covered by thin eschar. Evolution may be rapid, exposing additional layers of tissue even with optimal treatment. but in your case it is different this may be due to a blood clot or tendon injury or a small fracture any way it has to be investigated (xray,CT,MRI) before coming into a conclusion. hope this explains in detail