Baby measuring ahead

So I have had 3 anatomy scans done and in all of the scans I have measured 2-3 weeks ahead. My doctor does not do growth scans or measure my stomach he just checks to see if she has a heart beat. Is that normal? I’m 31 weeks 4 days according to him and with the anatomy scans I’m almost 34 weeks. He himself only measured my sac once and I was only 7 weeks. Should I expect my babygirl sooner than my due date of April 28th which my doctor told me but the scans say my due date is April 15th