Ovulation pred kit came + on 29Nov. Concieved that day. Today on jan4 abdom U/S says only 6W2d preg and can see only ges sac no baby. Is it normal?

OPK Kit/ conception? Ovulation prediction kits only determine the presence of LH, the hormone which causes ovulation. Actual conception can occur 2-3 days later, since sperm and egg can live prior to actual fertilization for 2-3 days. Your U/S may only see a sac at this point, so get a repeat U/S in about 10-12 days. The fetal heart should be present at that time.