Have Pre Diabetics. Feeling Tired Always, Following Diet And Exercising. What To Do?

I'm 41 yr. old female. I'm about 30 lbs over my max weight. I've been exercising in the gym at minimum 3 times a week Since January and playing sports 1 to 2 days a week. I have been diagnosed with pre diabetes and have modified my diet. I haven't eliminated all sugars and carbs, but I've reduced my intake by 50-75% what it was. SInce January, I've lost 8lbs. My workout today began with a 15 minute run on the treadmill, 30 minute full body strength training followed up by laps in the pool. I haven't swam laps in years. After the first lap, I felt somewhat sick to my stomach. However, I pushed myself to slowly complete 10 laps. After, i showered, dressed, and left the gym. I became more and more lightheaded. And while driving home I felt my legs and and arms go number - all the way to my finger tips. It became more difficult to concentrate. I stopped at a convenience store and it took all my concentration to go in, purchase some chocolate and protein/carb bar. I ate the food inside as I was nervous as to how I was reacting since my workout. After consuming the food I sat in my car for almost 30 minutes. I had to take slow deep breaths to keep in control of myself. Slowly the numbness began to recede. My hips and shoulders were last to feel normal. After the 30 minutes I felt I could concentrate enough to continue home. At home I still felt weak. I slowly ate a big meal and have been resting since. Although i feel tired, I am not experiencing any of the extreme symptoms from earlier. There is not doubt I'll make an appointment and see my doctor but it is safe to assume I'm out of any immediate danger?