Final answer:
Diana is most likely suffering from postpartum depression, a mental health condition presenting with symptoms like sadness, energy loss, and feelings of worthlessness after childbirth.
Step-by-step explanation:
Diana likely is suffering from postpartum depression. This mental illness is characterized by a range of depressive symptoms which can include sadness, a lack of energy, feelings of worthlessness, and additional distressing emotional states. These symptoms can emerge within the first few weeks to months following the delivery of a child, as noted in the case of Diana, whose symptoms manifested within 3 months post-delivery and have been persistent for 2 weeks.
According to research such as the study by Wisner et al. (2013) and the review by Fields (2010), postpartum depression has significant implications for early mother-infant interactions, parenting, and safety. It's essential for individuals experiencing symptoms such as Diana's to seek professional help, as effective treatment is available and can significantly improve outcomes for both the mother and her child.