flip, perhaps a good way for you to look at it is that people live WITH diabetes, they rarely die FROM diabetes.
when you get to see your gp he will probably initially do a very simple urine test which will involve you peeing in a bottle, into which he'll dip a small stick which will change colour depending on what's in your urine. IF (big if here) he thinks it's worth it, he may then do a small finger prick to test your blood to see what your blood glucose level is.
in the unlikely event that you do have diabetes, type 1 or type 2, you're not going to come to any harm waiting till monday.