the HCg levels should have indicated a closer look ... most "normal" pregnancies just double or slightly over ..every 48 hrs .. a slower rise or rapid extreme rise is usually indicative of an issue . My dr had me in for a Trans vag U/S at 4 weeks .. even though he didnt expect to see anythign at all he wanted to be cautious .. I have always had lower end hcg in my pregnancies but mine have doubled ... just slightly more .. I hope that you are indeed pregnant again and that it sticks to term