hey there
I haven't had hallucinaciations but there have been times I have had very vivid I guess daydreams where something horrible happens. I am sure if the bus had hit the man they would have stopped and everyone would have noticed. Maybe by the meds you are on or your specific condition you are more prone to thinking of things like that?
I would talk to a doc about this and dont be embarassed because if you cant say what really is going on they cant treat you.
If you can maybe talk to your mom. say you know she would not hurt the dog but you had some kind of illustion that she did? maybe she will be able to help you and understand, she is your mom. and do you have a good relationship where you think you can trust her with that? I know its scary but sometimes you have to take some risks to get the right kind of help and that does not mean you are crazy sometimes meds make you see things, you never know.
well good luck and try to find person to get you the therapy. We are all hear to help!
Leomia
Hallucination? Soz bit long... 
