4 weeks and negative thoughts

I’m currently 4 weeks and my anxiety is so bad I could cry I’ve had 1 miscarriage before I had my son and that’s always in the back of my mind I just want to be happy and celebrate bring a new little love bug in to the world but all I can think about is the what ifs…. I’m just hoping and praying that the baby has a heartbeat at my 8 week ultrasound