Hi, I read your query and can understand your concern regarding your becoming unresponsive. Stress can manifest as multiple things. A person can respond to stress in multiple ways. Many people become anxious and start having palpitations. Becoming unresponsive is not uncommon too. It is termed as a dissociative episode. However, sudden unresponsiveness can be due to multiple other reasons as well. Conditions like syncope also lead to fainting and unresponsiveness. You have mentioned that you have had blood tests in the past (which came out to be normal). I would have liked to know what blood investigation were done. In any case, an electrocardiogram for cardiac status and a complete blood count will be needed. If it comes out to be normal, you can seek a psychiatric consultation for further management. If it was an one off episode, trying to keep yourself relaxed, regular exercise would suffice. In case it has happened before or you feel anxious or stressed continuously, treatment with selective serotonin reuptake inhibitors like paroxetine can be considered. Hope this information was helpful. Best wishes.