Final answer:
Priscilla's behavior suggests Bipolar disorder, characterized by alternating periods of depression and manic episodes, which are indicated by her extended time in bed followed by impulsive spending.
Step-by-step explanation:
Priscilla's behavior of spending a significant amount of money impulsively, after a period of staying in bed for an extended timeframe, suggests that she may be displaying symptoms of Bipolar disorder. Bipolar disorder is characterized by periods of depression, evidenced by the weeks spent in bed and then periods of manic or hypomanic episodes, which could be represented by her sudden impulsive behavior such as purchasing a three-thousand-dollar plane ticket and planning a shopping spree with most of her savings. This alternating pattern of depressive and manic episodes fits the criteria for Bipolar disorder more closely than the other options provided.