While the pasta is almost done cooking heat the olive oil in a large skillet over medium-high heat. Add garlic and cook for 30 seconds then add the shrimp and season with salt and pepper. Cook until opaque throughout, about 5minutes. Add pasta mixture and 1/4 cup of pasta water to the skillet. Cook for 1 minute and then stir in the greek yogurt, feta, and dill. Mix well and if needed add more pasta water to the skillet until you are happy with the light sauce consistency throughout the pasta. Season with additional salt and ground pepper if needed, and serve.