I'm a 20 year old woman. I have blackouts and dizziness when I get up, not only when getting up fast. I've had this on and off for years, but it's increased in frequency and intensity lately. My bp is perpetually kinda low 85/50. Pulse 65 per minute. I used to occasionally get palpitations, got a cardiogram done. All clear from the cardiologist. I sometimes have sharp shooting pains in the head. Otherwise I'm A-ok. Any idea if there is anything I should be doing or concerned about?