How low can you go????

Last night, beginning at around 9 p.m Kalee began experiencing some unusual low blood sugars.  We could not pin point the reason..  There was no over bolusing, and she was doing some swimming and running earlier in the day, but nothing that would drop the blood sugar to 43 and keep it there for five hours.  I am not exaggerating, at all, when I say that we gave Kalee almost half a bottle of sugar tablets, 2 granola bars, crackers with peanut butter and jelly on them, 2 baggies of fruit snacks and 2 cups of orange juice (which my husband ran out at 1 a.m to purchase.) This was over a 4 hour time frame and her blood sugar would not go above 54.  I turned the insulin completely off (which I hate to do) and when she was still dropping, I pulled the pump right off of her, in fear that it had possibly malfunctioned and was still delivering.  It was not until about 2 a.m that she began to rise (only to 87)...  I continued checking her blood sugar throughout the night (or should I say, wee hours of the morning).  When she finally reached 100, I put another pod on her at the lowest basal of .05 and she still woke up in the 100 range??  I have absolutely no explanation for this.  Just when I think that I have experienced pretty much everything there is in the world of Type 1, something else gets thrown our way.  I will keep a close watch on Kalee throughout the day.  I was trying not to show my fear, but my anxiety was increasing with each blood sugar test that was not showing improvement.  I would like to say that I roll with the punches but some days (and nights) I would rather just punch something instead of actually rolling with them. ;)  Hope everyone has a nice weekend and any thoughts on what may have caused Kalee's outrageous lows are always welcome!