Heard a loud pop and then felt immediate, sharp stabbing pain in my calf. what could cause this? i also had a charlie horse in same calf yesterday

A pop suggests: Some type of injury, although that is not always certain. Are you able to move your foot up and down without pain? The most worrisome thing in the area is the achilles tendon, and if this ruptured you would not be able to walk very well. Could yesterdays charlie horse have been a calf strain? You may have had a strain that turned into a small tear if active. See your doc, too many variables.

Muscle tear: It may be a calf muscle tear. This painful injury typically occurs during activities that require sudden changes in direction like tennis. A pop may be heard, and there will be some swelling and bruising. Please have this properly evaluated.

Gastroc tear: The most common scenario to cause your symptoms is a partial tear of the gastrocnemius, one of the calf muscles. These can be very painful, but fortunately, tend to heal without aggressive/surgical intervention. Healing often occurs in 3-6 weeks. A heel lift and calf sleeve along with aggressive icing can relieve symptoms quite well in the first 1-2 weeks. Physical therapy can be helpful as well.