Sometimes early USG scan can't reveal details of feto-placental profile. Fetal node and cardiac activity is best documented by abdominal USG on 8th wk onwards or 6th wk in case of TVS.
Both the medicine are quite effective in developing stage of fetus and you should continue as per your doctor's recommendation.
Continue folic acid
supplements, protein rich diet, avoid long journey/ heavy work, maintain personal hygiene, take adequate rest and repeat scan after 4wks for detailed feto-placental well being. Do periodic check up and suggestive investigations.
If you need further consultation with me,then you can visit http://www.healthcaremagic.com/doctors/dr-soumen-patra/63326.