Lantus lows

I have 52 years, with 21 years of insulin dependent diabetes, 5 years using Lantus.

I use 3 rapid insulin bolus in day (pre-meals), and a lantus dose at night, some times I have hipoglycemias that can be easily managed with food.

8 days ago I get my SC lantus shoot at midnight and go to sleep, around 30 minutes later I feel a severe hypoglycemia (40 mg), who doesn´t relieved with food and lots of candies, I ended in a Hospital (ICU), getting repeated IV bolus of dextrose (the glycemia rise for moments and fall again), the situation relived a few hours later.  

No one knew what had happened, the next day I found the syringe I used for the Lantus injection clogged with blood.

The only explanation I found is that accidentally I inyect Lantus in a small vessel in my leg, but is a possibility that has to be pointed in the literature of  Lantus because of the serious complications it can have.