禁食42小時候血糖降到2.7， 2.5， 請醫生級別的大俠給評論，謝了先！

最近尿頻實太嚴重了，失眠一直都是斷斷續續，有時候也是持續很低久。大概個把月那樣晝夜不眠。

最近失眠非常惡劣，試過所有的了都無效。強烈懷疑自己糖尿病前期，雖然fasting glucouse & random glucouse never really high, 5.1, 5.2, 5.4, etc., HA1C最近一次測試隨機的4.8%， 但是常常感覺自己不能吃升糖指數高的食物比如燕麥粥什麽的，因為吃了立刻頭暈無力。 懷疑自己有胰島素受阻。 剛剛試著fasting, will power is strong but after 42 hours fasting, I felt numbness in my fingers, arms and legs, spinal cord, I was scared, checked blood glucouse, it was 2.7, 2.5, I stopped fasting immediately after that. 

I asked my doctor to give me Glucouse tolerance test (75ml) but I want to wait a bit trying to do some self healing.  I couldn't handle the bad results at this time, that will only make me more worrisome. Can some doctors online comment what my issue is??  Thank you so much in advance. 

(Typing in Chinese takes forever for me. sorry the rest was in English)