Heart beat monitor?

Im a first time mom, currently 4 months preggy. Im enjoying the journey but i get too anxious too quickly during this journey 🫣 So, currently my appointments are scheduled like once a month, and on those weeks that I dont have appointments, I get really anxious about my baby. I keep thinking if a miscarriage might happen, especially when I couldnt feel the movements of the baby yet. Hence, im thinking of getting a heart rate monitor so i can check on my baby anytime my anxiety comes up. Has anyone bought a heart rate monitor before? How is it for you, did it help with reassuring you or its worst cause at times you cant detect the heart beat?? 🙃