Hi MTP,
Firstly try not to panic!! Easier said than done I know.
I was in exactly your shoes about 5 weeks ago, and had exactly the same thoughts. I was scared to eat anything at all before I saw the consultant and dietician.
There is a thread going on Gestational Diabetes which I'm just about to post on, so you should see it pop up quite near this one. There's a lot of useful info on there and meal ideas so its worth a look and there are a few of us discussing what we are doing/what stage we're at etc.
How far on are you? Are they getting you to monitor your blood sugar levels already?
I'm no doctor but as far as eating over the weekend I would just say be sensible. I cut out things like orange juice, biscuits etc (anything 'sugary') straight away, and apparently low GI meals are the best to stick to. Most carbs convert to glucose fairly rapidly, so possibly try to stick to mainly proteins and lots of veg etc.
Of course your body needs carbs so things like new potatoes with skin on, wholemeal pasta, granary/seeded bread, plain wholewheat cereals such as weetabix are the best things to stick to in moderation.
You'll not really be able to get a handle on it until you start monitoring your blood sugar and will see what works for you, as everyone's different.
The immediate consequences for you of having GD is that you will have to prick your finger with a lancing device (not as bad as it sounds) a few times a day and put the blood on a test strip which goes in a little machine and tells you what your blood glucose level is. You'll then need to record this in a book so your consultant can see how your levels are. How often/when you have to test will really depend on your consultant.
Initially I would have thought they will try and get you to control the GD with your diet (that's what I am doing at the moment) but they may need to put you on insulin. According to Brightonbleach (a poster on the other thread) this isn't as bad as it sounds either, but she would be better to tell you about the ups and downs of this.
The main POTENTIAL consequence of GD for the baby is that if they get too much sugar they can grown very big, meaning they can be difficult to deliver. Their blood sugars can also be a bit up and down at birth so they might need a little spell in special care while they regulate these. Your obstectric consultant will keep a close eye on you though and you should get extra scans to monitor the growth of the baby. It may mean they induce you early or give you a section depending on the growth.
Very important to remember is all of these things are a MIGHT not a definite, and try to stay away from google (Pot kettle black there cos I am terrible for googling!).
Also once you start monitoring your BS its a good idea to keep a food diary so you can see what works for you.
Hope some of the above helps, sorry for the very long winded and rambling reply!
Look forward to chatting in the GD thread. Let us know how you get on on Monday and any questions ask away - no guarantee I can answer as I'm pretty new at this myself but I'll try and I'm sure there are more knowledgable people than me out there.
L, x.