Supposedly to be 7th week based on my LMP, however scan shows Week 5 Gestation

#1stimemom #pregnancy Based on my LMP, my pregnancy is supposed to be Week 7. However, I went to a gynae to check and confirm my pregnancy, the gynae mentioned that the scan only shows Week 5 Gestation. My period cycle length is between 31-45days. Unsure if this is considered regular or irregular? Gynae asked if my period is regular and I mentioned yes as it comes every month however, I did not mention there's delays(i.e.: 1-2 weeks, 1 month) and sometimes on time. Then, the gynae told me that if it's regular then the baby is not good. Now, I'm very worried. #advicepls