6 week heartbeat

Had my first ultrasound at 6 weeks because I was experiencing spotting. I had a previous MC so they did a reassurance check for me. Low and behold a baby!!! With a heartbeat of 120 BPM. I am a week earlier than I had originally thought... but after hearing the heartbeat with a rate of 120, what are my chances of maintaining this pregnancy? Last pregnancy we saw the tiniest flutter but couldn’t hear it or measure it. Praying so extremely hard my bean sticks!