I have numbness all over the body inspite of normal blood tests. Why?

Hello doctor,

I am a 28-year-old male. For the past two months, I am having episodes of undermentioned symptoms: My arms start getting numb, then this numbness spreads to the scalp, face, then chest, abdomen and so on to legs and feet. I have had such episodes for 25-30 minutes about seven to eight times in the last two months. Thrice during these episodes fingers of my both hands curl inwards and get stiff. Extreme weakness starts during these episodes and this weakness continues for the next two to three days. There is no previous history of any such symptoms and also there is no family history. Blood tests, arterial blood gas analysis (ABGs), electrolytes, cortisol level, thyroid, electrocardiogram (ECG), everything is normal. A medical specialist also referred me to a psychiatrist for panic Attacks. However, after the investigation psychiatrist said there is no such issue. I consulted another medical specialist and he said that if everything was normal then these might be the signs of stress. However, I do not have any stress related issues.