Fainting/heart rate

Okay I don't normally post but I've had a rough few days and need support/advice. I'm 34 weeks and I've been feeling generally huge and out of breath. I prepared for that. Then yesterday I was talking to a patient, I'm a PA, and I felt over heated. I stepped out the room cooled down and went back but I got extremely light headed and started to black out. I didn't and got to the door, well I hit the door, and got to the hallway. Nurses were there and I got cold rags and water. Heart rate was 115 and bp was fine. I felt like crap the rest of the day but had an ob visit scheduled for this am. Finished my day and went home early. Got a blood pressure machine and my blood pressure was only slightly elevated twice but my heart rate was in the 120s all day. So went to the ob and he did a quick measuring and heart beat check on the baby and told me to follow up with cardiology. I had heart surgery when I was two so I had cardiac clearance early into pregnancy and baby has had two level two ultrasounds to make sure she is fine and she is. Called cardiology and they can't get me in until September. You know after the baby is due. Told me to go to urgent care. Just frustrated. I know the medical system. And I know what I'm feeling is likely normal but come on! I need some reassurance. I would never do that to my patients.