You searched for: “thermalgesia
thermalgesia, thermoalgesia (s) (noun) (no pl)
High sensibility to heat; pain caused by a slight degree of heat: When the ligaments, tendons, and muscles swell due to heat or hot weather, it is referred to as thermalgesia. A person is dehydrated and the joints lose water or fluids.

Thermalgesia is a condition in which the application of heat produces pain.