What Does Sinus Rhythm ST T Changes In The Septal Lead In My EKG Report Indicate ?

Question: I am a 34 yo female that was diagnosed with mastocytosis in early 2008. I've managed to go 3 years without medications but this year it seems my symptoms have gotten worse and in April I started taking Singulair 10mg and Allegra 180 mg every day and Zantac as needed. Recently for about a month and 1/2 I've been experiencing dizziness/lightheadedness mostly in the afternoon, but occassionally in the mornings. It's usually when I'm sitting at my desk or lying on the couch, not upon standing or anything. I've had some chest pains that I can't explain, more like gas pains or cramps in my upper chest area. For years I've experienced a butterfly feeling with my heart but it's always been pretty sporadic. Lately the feeling feels more like my heart is flopping and it's happening more frequently. Once a day but more like every other day now. When I was first diagnosed with masto, I had a cardio work up (EKG and ultrasound) and everything looked great, but the doctor did find a heart murmur that I knew nothing about. My PCP examined me today and thought he heard something a little weird with my heart so he performed an EKG. He ran it twice and the report he gave me stated: Sinus Rhythm ST T changes in the septal lead, Changes are abnormal for age and sex. Can you tell me what this could potentially indicate? He is sending me to a cardiologist. I know anemia and dehydration can cause issues, I don't drink enough liquids so is it possible that's what's causing the dizziness? Is this EKG something to be concerned about? I do not drink alcohol, I do not have a history of high blood pressure and I am otherwise healthy except for the mastocytosis. I am not overweight. I've been recording my blood pressure over the last 5 days and it has been lower than usual for me. A copy of my EKG is attached in a separate e-mail.