Panic Attack: This condition is characterized by intense fear or discomfort, often accompanied by symptoms such as palpitations, sweating, trembling, shortness of breath, feeling of choking, and numbness or tingling sensations. The symptoms described, including near syncope, anxiety, numbness, and tingling in arms and around the mouth, are classic for a panic attack. The sudden onset and the combination of physical and psychological symptoms align well with this diagnosis.

Hyperventilation Syndrome: This condition can lead to symptoms like lightheadedness, near syncope, numbness, and tingling around the mouth and in the extremities due to respiratory alkalosis from deep or rapid breathing, often triggered by anxiety.
Anxiety Disorder: While panic attacks are a type of anxiety disorder, other forms like generalized anxiety disorder can also present with similar symptoms, though they might be less intense or episodic compared to panic attacks.
Vasovagal Syncope: This is a common cause of fainting spells and near syncope, often triggered by stress, pain, or prolonged standing. It can be accompanied by symptoms like numbness or tingling, though these are less common.

Cardiac Arrhythmias: Conditions like supraventricular tachycardia (SVT) or ventricular tachycardia can cause near syncope and may be associated with anxiety and tingling sensations. These are potentially life-threatening and require immediate medical attention.
Myocardial Infarction or Acute Coronary Syndrome: Though less common in younger populations, chest pain or discomfort, shortness of breath, and other symptoms including numbness or tingling can occur during a heart attack. Immediate diagnosis and treatment are crucial.
Stroke or Transient Ischemic Attack (TIA): While less likely given the symptom complex, it's essential to consider stroke or TIA, especially if there are focal neurological deficits. Prompt recognition and treatment can significantly impact outcomes.

Multiple Sclerosis: An autoimmune disease that can cause a wide range of neurological symptoms, including numbness, tingling, and vision problems. While it's a less likely cause for the acute presentation described, it should be considered in the differential for chronic or recurrent symptoms.
Peripheral Neuropathy: Conditions affecting the peripheral nerves can cause numbness, tingling, and sometimes anxiety. However, near syncope would be an unusual presenting symptom.
Hypocalcemia or Hypokalemia: Electrolyte imbalances can cause muscle weakness, tingling, and in severe cases, arrhythmias leading to near syncope. These conditions are less common but can be identified through laboratory tests.