Cook the cheese tortellini according to the package instructions. Once done, reserve at least ¼ cup of the pasta water, then drain the tortellini.
Season the shrimp with ½ teaspoon of salt and ¼ teaspoon of black pepper. In a large skillet, heat oil over medium heat. Add shrimp and cook until opaque (about 2-3 minutes). Set aside.
In the same skillet, add shallots and garlic. Cook for about 2 minutes, stirring often, until soft and fragrant.
Pour in the white wine and increase the heat to medium-high. Cook until it evaporates, scraping the bottom of the pan to lift any stuck bits.
Lower the heat to medium. Stir in the heavy cream, thyme or basil, and reserved pasta water. Add the cooked tortellini and green peas, then simmer for about 2 minutes.
Return the cooked shrimp to the skillet and simmer until heated through, about 1-2 minutes. Stir in the lemon juice, lemon zest, and grated Parmesan until creamy. Taste and adjust seasoning with salt, lemon juice, or more cheese as needed. Serve with chopped parsley.