Slow growth

Ka

Went to see my baby this morning. According to the app I am 7 weeks and 4 days. Saw the baby but we were not able to hear the heartbeat. Last week we were not able to see the baby, only the yolk sac. Last week it measured 5 weeks and 4 days, today the baby measured the same. Has this happened to anyone? It seems so sloooow!