What is a sore red bump with little blisters on the palm?

A sore red bump with little blisters on the palm could be a sign of a condition such as dyshidrotic eczema, which often leads to itchy, fluid-filled blisters. It may also be due to contact dermatitis from an allergic reaction or irritation. Other possibilities include hand-foot-and-mouth disease or a viral infection. It's best to consult a healthcare professional for an accurate diagnosis and appropriate treatment.