Doesn't gestational diabetes usually appear in mid to late pregnancy?

The reason I ask is b/c I suspect that I was a diabetic for about a year now--my doctors recommended I be tested for it, and I never was until I found out that I was pregnant. I failed the test and they diagnosed me as a gestational diabetic when I was only 6 weeks pregnant. I thought that gestational diabetes only appeared in late pregnancies, so now I'm wondering if I had diabetes pre-pregnancy or it this could really be only gestational diabetes. Any advice is appreciated.

I was tested b/c of having two babies that were over 9 pounds--I'm in my normal weight range for my height.

Although there is no way to know for certain, yes, I think you are right in that you quite possibly already had diabetes BEFORE you became pregnant. *Usually* people are more insulin sensitive early on in pregnancy, so if your blood sugars were elevated that early on, there is a very good chance you already had full blown diabetes.

I also suspect this because your doctors "recommended you be tested for it". Were you overweight prior to becoming pregnant? This greatly increases your risk for gestational and Type 2 diabetes.

You will have to see what happens. Even if it is "only" gestational diabetes, this puts you at a high risk of developing Type 2 diabetes in the future. Work on losing weight after your pregnancy, eating healthy, and getting regular exercise. In many cases, Type 2 can be prevented or controlled with lifestyle if caught early on.

There is no way to know for certain until after your pregnancy.

In rare cases, pregnancy can trigger Type 1 diabetes, the rarer non-preventable autoimmune kind that always requires insulin injections. This does not sounds like it applies to you, however.

I have type 2 diabetes and I had gestational diabetes too. All it entailed was a worsening of my normal diabetes. I was not seen by a doctor until I was 12 weeks, since my clinic wouldn't see me until that point (and yes, I did tell them I was diabetic.) So mine wasn't picked up until then. But they should have tested me sooner, so be very glad you've caught it earlier. The first 12 weeks are the most crucial for the baby, since that's when the major parts form. It is extremely important to have tight control of you blood sugars during this time.
As to why it's normally diagnosed later, that's because the test is normally done later. They may have tested you earlier based on the suspicion that you already were a diabetic or they may have detected something in another test that caused them to suspect the diabetes.
Being a pregnant diabetic is a full-time job, even my doctor agrees with that. It is hard work to take care of yourself, but your reward will be a healthy baby, so it is worth it.
After your pregnancy, you may have a "honeymoon period" where the diabetes seems to be gone or much better. After that period passes, you will need to be tested again, and then they can determine if you truly are diabetic.
Good luck and take care!