Were the joints/blunts laced with another drug?

I think you blacked out from lack of oxygen it happened to me once I hit my bong really hard(like I always do) and went to stand up to get a soda while holding it in and got a feeling of falling back even though I wasnt then everything started to go black and I couldnt hear anything really like you said and I fell forward and went unconscious I was only on the ground for probably 30 seconds max but it was crazy. I have seen this happen to people taking "knifers" of hash. I was smoking for many years daily before this happened and had seen people do it but never thought it would happen to me.