Preheat the oven to 425°F. Line a baking sheet with parchment paper.
Place the shrimp on the prepared baking sheet, drizzle with the butter, and toss with the Old Bay seasoning. Spread the shrimp in a single layer and roast until pink, curled, and cooked through, 5 to 7 minutes. Allow the shrimp to cool completely.
Bring a large pot of salted water to a boil. Add the pasta and cook for 1 minute longer than the package directions. Drain, rinse with cold water, and let cool.
In a very large bowl, whisk together the mayonnaise, sour cream, chives, lemon zest, lemon juice, hot sauce (if you like), black pepper, and salt. Fold in the shrimp, pasta, celery, and bell pepper.
Serve at room temperature or chilled.