Heat olive oil in a medium pan. Add onion and cook until soft, about 5 minutes.
Add garlic and red pepper flakes and cook 1 more minute.
Add diced tomatoes, tomato paste, sugar, oregano, and heavy cream. Simmer for about 3 minutes.
Add shrimp and salt and pepper to taste. Cook until shrimp are pink, about 2 to 3 minutes.
Sprinkle olives and feta cheese on top and serve.