Yes--I have this problem. Its more likely to happen if you drink, but I've had memory blackouts on one with no alcohol as well. Scary.
The thing that scares me about it is that sometimes I'll lose memories that happened the day before I took it as well--e.g. I have forgotten that I met people the previous day.
You drank alcohol didn't you?
You might be allergic. Stop taking them and see the doctor that prescribed them.
Did you take anything else/did you consume alcohol?
does not generally cause that response but you may have a exceptionally low tolerance.