big or normal

Had a growth scan at 31 weeks because my first was very small (5lb 11oz at full term) and was told baby is 3lb 11oz already 😱 just wondering if anyone else thinks thats big seen as got 9 weeks left of growing They didnt say it is big just they not concerned about it but im worry now thinking im going to have a huge baby i also have pregnancy related diabetes so know that there is a chance of a huge baby