My fetus is measuring 7 weeks but gestational sac is 1 week behind. is that bad? heartbeat is 140bpm. is there anything i can do to help it grow?

Normal pregnancy: Just relax and don't worry . You will probably be fine. Worrying makes matter worse. Time will tell you. Subsequent us will give better idea in second trimester.

Unclear results: That does not really make sense. I would ask your doctor to clarify the sonographic findings with you to make sure you understand what is going on with your pregnancy.