What does Judges 15:11 mean?

Three thousand men from Judah went down to the cave at the rock of Etam and said to Samson, 'Don’t you realize the Philistines are in charge of us? What are you doing to us?' Samson answered, 'I’m only doing to them what they did to me.' Judges 15:11 - Modern Text Bible

(The people of Judah confront Samson because his actions have brought trouble from the Philistines, who rule over them. Samson insists he’s just paying them back for what they did to him.)