Please...

Went to the ER due to cramps (no bleeding though). My last period was September 16th, which will make me 8 weeks tomorrow. I went a few days ago, at 7 weeks and 4 days. The ultrasound showed the baby was the size of 5 weeks 3 days and the heartbeat was 91. So am I 5 weeks or am I 7 weeks and the baby is just 2 weeks behind. If that’s the case, should I be worried that the heartbeat is 91? My HCG was 7,500. Google says both the heartbeat and HCG level is low for where I’m at. I go back to dr. Tuesday and I’m so terrified. You ladies are so strong and I’m so glad we have eachother to help through tough times. Please pray for me... we tried for this baby for a year ...