No. The heart is the first visible sign of life in a fetus, on an ultra sound. It can be seen as early as three weeks with a vaginal ultra sound. If a heart beat is undetectable by dopler, or other sound amplification, an ultrasound is ordered for confirmation. Sorry. Good luck.
You can say that an ultrasound can be wrong when it is done with a wrong technique and at bad time. For example if one feel urine time then ultrasound shouldn't be performed. There is no harm in performing another ultrasound. There are cases when a pregnant woman goes for ultrasound and founds nothing in the picture so you shouldn't be worry about. Just take an other ultrasound.