Hi, I understand your concern, as though you are young and skinny, so your blood pressure tends to be down. However, it must be confirmed whether the gauging technique is correct, if the device is calibrated properly, if the cuff has the width suitable regarding the circumference of your arm. All these parameters might incur wrong pressure readings down. In case your level of pressure is really low, we will have to check if the symptoms you are related reported low pressure or not. The most common cause of low pressure in young is vasovagal syncope. However, your description of the symptoms are not compatible with this clinical situation. If the low blood pressure is confirmed, I suggest you look for a Cardiologist for further investigation. I hope I have answered your question. In case of doubts, I am available for further questions. Have a good health.