actually you seem to of mixed Bast the cat goddess of music and dance [and later sex] with the healing and war goddess Sekhmet who has the body of a woman and the head of a lioness. she too has many sides and attributes [like the belief her breath is the desert wind] she can be kind but a fierce defender
Egyptian mythology can be very confusing as each region and city had its own gods and myths. so while similar in nature, the deities were different in the tales. in lower Egypt it was Bastet and in upper Egypt they had Sekhmet. one creation story speaks of Bastet being Ra's daughter or wife and he turns her into Sekhmet. the one i go with [mostly because i heard it first] speaks of Ra growing angry with the rebellion plots so he took his eye and created Sekhmet, sent to destroy his enemies. her blood lust grew great and he had to trick her to make her stop. he then turned her into Hathor.
there was a time when it was believed they were one and the same, but they are two different deities.