Heart palpitations and possible anxiety? Help?

Recently I have had heart palpitations, been feeling light headed and also felt twitches. I struggle to get to sleep and when I do I have a jerk that wakes me up. After seeing the doctor he said its probably anxiety related. The thing is I haven't been feeling anxious. I explained this but he said anxiety can sneak up on you from worries on a subconscious level. With me moving to university its an explanation, however am usually laid back and cool about things such as this. Tomorrow am going for a heart scan and a blood test. I was just wondering is this anxiety, and would just like a like information on it. Thank you