In a large pan, saute the chicken in vegetable oil over medium high heat until cooked through and no longer pink. Remove the chicken from the pan. Reduce the heat to medium and add the butter to the pan. Add the carrots, onions and celery and saute until soft, about five minutes. Add the flour, salt, pepper, celery seed and poultry seasoning to the pan and cook for 2-3 minutes, stirring frequently. Slowly add the chicken broth and milk to the pan, stirring constantly. Add the chicken and the peas. Simmer until mixture thickens. Remove from heat. Preheat oven to 425. Line a pie pan with one of the crusts and add the filling. Cut several slits into the other crust BEFORE topping the pie. Tuck the top crust under the bottom one around the edges and pinch to seal. Bake in preheated oven for 30-35 minutes. Cool 10 minutes before serving.