It is natural to feel concerned if your scan at 8 weeks of pregnancy reveals that the baby is measuring only 6 weeks and no heartbeat was detected. However, it is important to remember that every pregnancy is unique, and there can be variations in fetal development. In some cases, the dates may have been miscalculated or ovulation could have occurred later than expected. It is also possible that the embryo stopped developing, resulting in a miscarriage. Your doctor will likely recommend a follow-up scan to monitor the situation and determine if there are any changes in fetal growth or heartbeat. It's essential to stay in close communication with your healthcare provider for guidance and support during this time.