Toss shrimp with salt, pepper, Cajun seasoning, and oregano. Cook in a large skillet with olive oil for 2-3 minutes. Set aside.
In the same pan, brown sliced sausage; set aside.
Cook pasta in salted boiling water until al dente; drain.
Lower heat, add more olive oil to the pan. Sauté onion, bell pepper, Cajun seasoning, brown sugar, and a pinch of salt until softened.
Add garlic, cook for 30 seconds. Stir in crushed tomatoes, chicken broth, and heavy cream. Simmer for a couple of minutes.
Add Parmesan, stir until blended. Add cooked pasta and sausage, heat through (2-3 minutes). Salt and pepper to taste.
Finally, add the shrimp. Serve sprinkled with chopped parsley.