Advice from who is has has been pregnant?!

I am barely 5 weeks pregnant and went to the ER last night because I have been having sharp pains in my sides and I did have light pink spotting but only the one time. The ultrasound tech was nice and turns out the sharp pain was from a cyst I also cramp off and on which I hear can be normal they barely saw the baby but it is there it’s just really tiny and the doctor said the heartbeat is at 83 which is below normal and basically told me I’m going to have a miscarriage!!! I came home crying like why would you say that when you don’t know for sure! I feel a tad better talking to my friend who worked at an obgyn for 10 years. Has anyone lost a baby due to the heartbeat being lower than normal? Or did it get stronger and survive?