Low fetal ❤️ beat (5-6 weeks)

I’ve had two ultrasounds back to back, one from a free clinic and one from an OB. According to my most recent ultrasound im 6 week and 1 day today. My baby has shown a very low heartbeat during both appointments. (I don’t want to disclose the bpm because I don’t need any negative or scary comments. I know, I have already had my OB’s opinion and he told me not to freak out because it’s early. I’m done worrying about it.) She’s grown 1mm in 2 days since my first ultrasound (measured CRL was 4.9 mm) and the bpm has increased very slightly but was still on a very low end. Ive had no bleeding, very mild cramping, sore as hell boobs, stinky gas, and cravings for everything. I’m just wondering if anyone else in this same boat with low fetal heartbeats during early pregnancy (5-6weeks).