Miscarriage after hearing a heartbeat?

I'm so torn my nurse and the ultrasound tech had me on cloud nine after a very stressful week. Spotting before Thanksgiving getting bloods drawn for hcg levels to no spotting but then cramping. The waiting game between follow up bloods and results to lower then normal levels to anticipating ultrasound in hopes to see a heartbeat.... Which we saw 😍. Little peanut has a heartbeat of 118 the ultrasound tech said she's hopeful it's within range so not a loss and still early but she is able to measure a heartbeat. Nurse said even if levels are lower then average I'm still in normal range. Doctor however said yes I'm still ok today but anything can happen and be prepared for the worst. I'm not spotting anymore no more cramps and we seen a heartbeat. Has anyone had a similar story with a positive outcome or even one where it wasn't favorable and resulted in a miscarriage but your working through it. I'm going stir crazy now trying not to stress cause as of right now today baby is ok. Thanks for your input ladies