Measuring 40 weeks at 33+5....advice please.

I've just been to see my midwife and she measured me at 40 weeks when I'm only 33+5 weeks, I have a growth scan tomorrow and I've got to go and have my blood sugar/glucose taken at the hospital as they think I could have developed diabetes. The midwife has told me that if baby is as big as they think she is then I will be induced which has made me feel really nervous and overwhelmed.