What is the reason for feeling easily tired after hitting a tire once?

Patient's question:

Detailed medical condition and consultation purpose: Hello everyone! I want to ask is, my girlfriend has been feeling much worse since having a miscarriage, getting easily tired, and mainly, she now experiences dizziness after sexual activity. I want to confirm if it's due to anemia or other reasons. If it is, how should it be treated? Thank you!~
Duration and course of the current illness: Over a month
Current general condition: Mainly general weakness and dizziness
Medical history: None
Previous diagnoses and treatment history and effectiveness: None
Auxiliary examinations:

Doctor's answer:

Hello
You can have a blood test to check your blood routine.
Anemia refers to hemoglobin levels below 120 g/L for adult males, 110 g/L for adult females, 100 g/L for pregnant women, 145 g/L for newborns within 10 days, 100 g/L for infants between 10 days and 3 months, 110 g/L for children aged 3 to 6, and 120 g/L for children aged 6 to 14. It is generally considered that anemia exists.
　　Common types of anemia in clinical practice include iron-deficiency anemia, megaloblastic anemia, aplastic anemia, and hemolytic anemia. Additionally, hemorrhagic anemia can occur, as well as anemia associated with chronic inflammation, liver disease, connective tissue diseases, malignant tumors, and endocrine disorders. After anemia, hemoglobin levels decrease, reducing the blood's oxygen-carrying capacity, leading to hypoxia in tissues and organs throughout the body. The presence and severity of anemia symptoms depend not only on the nature of the primary disease but also primarily on the degree and rate of anemia, as well as the patient's age, the presence of cardiopulmonary diseases, and the compensatory capacity of the cardiovascular system. Early and common symptoms of anemia include fatigue, weakness, dizziness, tinnitus, memory loss, and poor concentration. Pale skin and lack of radiance in the face are the most common objective signs of anemia. However, judging anemia based on skin color often has errors. It is more reliable to assess the color of the conjunctiva, oral mucosa, and nail beds. Anemic patients may also experience palpitations, rapid heart rate, shortness of breath after exercise, loss of appetite, nausea, and abdominal distension. Severe cases may lead to ankle edema, low-grade fever, and protein