Bring a large pot of salted water to a boil. Add the fettuccine and cook according to package instructions until al dente. Reserve ½ cup of pasta water, then drain the pasta in a colander and set aside.
In a skillet, heat the olive oil over medium heat. Add the minced garlic and sauté for about 1 minute, until fragrant but not browned.
Add the shrimp to the skillet and cook for about 3-4 minutes, turning occasionally until they turn pink and opaque. Remove the shrimp from the skillet and set aside.
In the same skillet, add the heavy cream and bring to a simmer. Stir in the grated Parmesan cheese, cherry tomatoes, salt, black pepper, and red pepper flakes (if using). Mix well and let the sauce simmer for 3-4 minutes until it thickens slightly.
Add the cooked fettuccine and shrimp back into the skillet with the creamy sauce. Toss gently to combine, adding reserved pasta water as needed to reach the desired consistency.
Taste and adjust seasoning if necessary. Remove from heat and garnish with fresh parsley before serving.