I'm so sorry you're going through this. My girlfield didn't see a heartbeat until 9 weeks, but with each weeks ultrasound, they were seeing growth, so if anything from that weeks time frame they should have seen some kind of growth.
But please, please don't give up hope, I had 4 miscarriages and 1 Ectopic and I delivered my son at the age of 41 and he is a healthy 21 lb, 6 month little felloe. It will happen - "Won't it Amanda" Don't give up on your hopes and dreams, this will happen, just stay positive and don't give up, it truly will happen.
Good Luck and Take Care
I, too, am so sorry to read that you are going through this. I understand how you feel, as I went through a similar experience. I was with my first husband since my early 20s and we were together for almost 13 years and married for the last 6 years. I was ready to have a baby in my early 30s but that's when my first marriage started falling apart. He had an office affair and we divorced. He also had problems.
Fast forward through a difficult 30s and back dating like a single gal...I met my current husband when I was 40. We had three miscarriages. All were conceived naturally within the same month of trying. I just married him and I am now 42. And we still want a baby.
I well understand the irony. I'm sorry you are going through this pain.
I am so sorry. I too have had 5 miscarriages and I know how heartbreaking it is. Yvette and your Dr. are right. At 7 weeks a fetal heartbeat should be visible. However, for peace of mind there is absolutely nothing wrong with getting a second opinion. I did that once and although the outcome was the same if helped me make peace with it. I am not sure if your Dr. offered you medication to help things along, but there is no panic. Do what you need to do to be sure, and again I am so very sorry.
I'm sorry for what you are going through. I went thru 5 miscarriages myself. I think your doc is probably right. At 7w2d you should be able to see the fetal heart rate on the ultrasound. And if you're not seeing it then it's not a great sign. They may have you come back in a week, but usually after the yolk sac is seen you should see the heartbeat shortly thereafter. It's hard to sustain a pregnancy in your 40s. Sometimes it's not so hard to get pregnant, but getting out of the first trimester can be challenging. Not to say that it can't happen as it certainly can.
Regardless of when you ovulated, had your lmp, the fact that they saw yolk sac, they should see the heartbeat within the following week. Sorry I'm not giving you much hope here. I am very sorry for your loss and I know the devastation and the sense of loss you are feeling.