At 5 weeks of pregnancy, it is not uncommon for an ultrasound to only show a gestational sac and yolk sac without a visible fetal pole or heartbeat. This is because the fetus is still in its early stages of development. It's important to remember that every pregnancy is different, and some may progress at a slightly slower pace. However, if you are concerned about the lack of fetal pole or heartbeat, it's best to consult with your healthcare provider for further evaluation. They may recommend additional ultrasounds or tests to monitor the progress of your pregnancy. It's also helpful to hear from others who have had similar experiences, as they can provide support and reassurance during this time.