Sir/Mam I am 30 years active man, I m physically very active working in army , many times I feel like very weakness and it feels like core weakness simultaneously very unwanted thaouts are comminng in mind like I will die or something , I am unable to even stand , and gas also forms, I feel like irritation. However this all remains for a day nd that's it but it happens many time, my head become heavy and I feel very low,  My Routine  blood tests are normal ecg echo normal. What could be the exact cause plz suggest the best