You should really get your midwife to get you to have the glucose tolerance test or at least get your doctor to check your blood sugar level (and if he/she is concerned arrange a glucose tolerance test). If it is high and left untreated it can cause organ damage in early pregnancy and an oversized and/or diabetic prone baby in latter pregnancy.
I know this as its my 2nd pregnancy and very early on my sugars were high too and they needed to be controlled by insulin. In my 1st pregnancy I was diagnosed having high blood sugars (gestational diabetes) at week 28 and it was controlled by diet and insulin. The sugar level went normal after the birth of my 1st child but as I said, in my 2nd pregnancy the sugars have gone high again. The doctors at the hospital are keeping a close eye on me.
Go see a midwife or doctor to check this out if you are concerned. Dont just try and 'treat' yourself. If your sugars are high, you may need insulin. At the very least the diabetic nurses/dieticians at hospital can give you advice on what foods to eat and not eat too.
Good luck!