I think I'm pre-diabetic--why am I shaking?

I think I might be pre-diabetic. Have had some symptoms, so I bought a meter and have been testing my blood sugars every morning, after a 9-10 hour fast. My morning glucose levels have been around 111-115, which, from what I've read, is on the high side but not diabetic high. So I started trying to eat better and exercise more. More fruits and vegetables, I eat a salad for lunch with baby spinach, oven roasted chicken, some cheese and chick peas, FF low cal dressing. I've been staying away from bread and sugar (I'm a big processed sugar person, too many cookies, brownies, etc), though I did eat whole wheat pasta the other night. The thing is... I found a website that told me how to test myself, to see if I might be diabetic. she said to fast overnight and take your blood sugar level in the morning. Then eat something high carb, at least 60-70 grams, and test and 1 and 2 hours afterwards. I ate two pieces of toast and coffee with FF creamer and truvia sugar substitute. My numbers were high-- 184 (1 hr) and 148 (2hrs). The entire two hours, however, I shook like a leaf. I feel really wired, and I don't normally feel this way. i usually only drink coffee for breakfast and don't usually feel hungry until around lunchtime.

Well, I've just eaten lunch. A baby spinach salad with string cheese, oven roasted chicken breast, cucumbers, and chick peas and FF low cal dressing, and I'm shaking again, a very low sort of trembling. I don't FEEL good. My head feels funny... my mind is all over the place. I feel very...spacey, hard to focus. I don't feel this way when I eat a normal meal. I think I get sleepy when I eat too many carbs (from what I've read anyway, that would be my guess on why I get so sleepy after meals). The other night for dinner I had one breadstick with my (whole wheat) pasta and I felt fine after dinner. Not tired at all, not shaky. Just...normal.

I do plan on calling my doctor on Monday (obviously they're not open now) but for the time being, I'm really curious... why do I feel this way? Why am I shaking like this? Am I doing something wrong?

Just trying to understand things a bit...am grateful for any info you more experienced people might be able to give me. :)

Thank you!