Postpartum Preeclampsia: This condition is characterized by the onset of hypertension and often proteinuria after 20 weeks of gestation, which can persist or develop postpartum. The patient's presentation of postpartum hypertension, heavy vaginal bleeding, and significant proteinuria (+30 protein) supports this diagnosis. Postpartum preeclampsia can lead to complications such as eclampsia, stroke, and HELLP syndrome, making prompt recognition and treatment crucial.

Deep Vein Thrombosis (DVT): The patient's right-leg swelling could be indicative of DVT, a condition known to be associated with pregnancy and the postpartum period due to hypercoagulability. The risk is further increased by immobilization, surgery (including cesarean delivery), and other factors that may have been present in this patient's recent history.
Postpartum Hemorrhage (PPH): Although the patient is 6 weeks postpartum, which is somewhat late for the typical presentation of PPH, retained products of conception or other complications could lead to delayed heavy vaginal bleeding. The mild anemia (Hb 10.4 g/dL) could be a consequence of chronic blood loss.
Pulmonary Embolism (PE): While not directly indicated by the symptoms provided, in the context of DVT and the hypercoagulable state of pregnancy, PE is a possible diagnosis that could explain some of the patient's symptoms if they were to present with respiratory distress or chest pain.

Pulmonary Embolism (PE): As mentioned, PE is a critical diagnosis to consider due to its high mortality rate if untreated. Symptoms can be nonspecific and may include shortness of breath, chest pain, or cough, which are not mentioned but should be investigated.
Septic Pelvic Thrombophlebitis: This rare but serious condition involves infection and clotting of the pelvic veins. It can present with fever, pelvic pain, and signs of sepsis, which are not explicitly mentioned but could be considered in the differential, especially if the patient shows signs of infection.
Amniotic Fluid Embolism (AFE): Although extremely rare and typically occurring during labor or immediately postpartum, AFE is a catastrophic condition that can present with sudden onset of hypotension, hypoxia, and either cardiac arrest or coagulopathy. It's unlikely given the timing but should be considered in any postpartum patient with sudden, severe symptoms.

Thrombotic Thrombocytopenic Purpura (TTP): A rare blood disorder characterized by clotting in small blood vessels throughout the body, which can lead to microangiopathic hemolytic anemia. It's a rare condition but could potentially explain some of the patient's symptoms, including anemia and thrombocytopenia if present.
HELLP Syndrome: Characterized by Hemolysis, Elevated Liver enzymes, and Low Platelet count, HELLP syndrome is a variant of preeclampsia and can occur postpartum. It's a serious condition that requires prompt recognition and treatment to prevent maternal and fetal complications.
Atypical Hemolytic Uremic Syndrome (aHUS): A rare, life-threatening disease that causes abnormal blood clots to form in small blood vessels throughout the body. It could potentially present with similar symptoms, including anemia and signs of renal impairment, although it is much less common than other diagnoses listed here.