Cook pasta according to package instructions in a pot of salted boiling water; drain and rinse reserving 1/2 cup of the pasta water. Set it aside for later.
While pasta is boiling, heat a large skillet on medium-high heat. Add 1 tablespoon of the olive oil to the pan and fry half of the garlic for 30 seconds; add the onions, and continue cooking until soft. Add the mushrooms and fry while stirring, until the mushrooms have browned. Stir through 1-2 tablespoons of water and cook them for a further minute. Transfer mushrooms to a plate and set it aside (keep any liquid leftover in the pan).
To the same pan, add the remaining oil. Sauté remaining garlic until fragrant. Add the shrimp and cook until they just begin to change color. Add the pepper flakes, paprika and salt.
Cook while stirring for a further 1-2 minutes to combine all the flavors in the pan. Add the mushrooms to the pan, stirring them through the flavors in the pan. Transfer the shrimp/mushroom mixture to the same plate the mushrooms were on.
Add the cream cheese and milk to the same pan and bring to a simmer while stirring occasionally, while breaking up the cream cheese. Allow to simmer for about 5 minutes, then add the cheeses. Once the cheese has melted through, salt and pepper to taste.
Add the shrimp/mushroom mix along with the pasta into the creamy sauce, stirring for 2 minutes on low heat. Add the reserved pasta water -- 1/4 cup at a time -- only if needed or until reaching your desired consistence. Garnish with parsley and serve!