Meanwhile, cook pasta according to package directions; drain.
Preheat a grill pan to medium-high heat. Season the shrimp with lemon pepper and garlic salt. Spray the grill pan with cooking spray and cook the shrimp until pink.
Toss together the pasta with butter and Parmesan cheese. Plate pasta, topping with mushrooms, shrimp and chopped tomatoes. Garnish with more Parmesan cheese. Serve with lemon wedges.