Does Steroid Injection Cause Unconsciusness?

I received a steroid injection at the hip yesterday for a sinus infection. About 3 minutes later, I fainted and was unconscious for a few minutes. It took another 30 minutes or so to regain normal sight and hearing. There are no more side effects other than bruising where I banged my head. I feel much better, though as far as the sinus symptoms. Why did this injection cause this and what is the type of steroid given for sinus infections?