Cook the rotini pasta according to package instructions until al dente. Drain and rinse under cold water to cool. Set aside.
In a large mixing bowl, combine the cooked shrimp, cherry tomatoes, cucumber, red bell pepper, and red onion.
In a separate bowl, whisk together the mayonnaise, sour cream, lemon juice, Dijon mustard, Worcestershire sauce, Old Bay seasoning, salt, and pepper until smooth.
Add the cooled pasta to the shrimp and vegetable mixture. Pour the dressing over the top and gently toss until everything is well coated.
Cover the salad and refrigerate for at least 30 minutes to allow the flavors to meld.
Before serving, give the salad a gentle stir and garnish with chopped fresh parsley.