Hello, Numbness of the tongue and feeling of lethargy may happen due to low blood sugar, vitamin B deficiency, anxiety or migraine, nerve damage. You are suggested not to skip meals, take food in time and adequate rest. Make sure your vitals are normal. Stay away from anxiety and stress (emotional and physical). You should get clinically examined by a GP. Get all required tests and investigations done to detect any developing blood clot that may cause medical emergency. You will be treated accordingly. Get examined by a Neurologist to detect nerve damage or developing neuropathy, Get Nerve conduction velocity tests, etc., done so that treatment can be started at the earliest. Stay away from addictions if any. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician