I met a man I thought was a vampire once. He drank blood.
Omg really? i have never heard of that, does he see his reflection in the mirror :D
I'm not sure about that part but usually they are known to drink the life essence of beings.
do they behave like real vampires? i cant imagine that vampires are real :D
It depends on what you mean by real. Vampires were popularized in the West and there is a lot of stuff that comes from popular media then there are the myths and legends of old.
I know that the word vampire originated from Serbian language, Serbia is really close to Transilvana, so i think thats where it all begun 
Is that right? Where was the first vampire from?
I think from transilvana nowday romania, vlad wanted to scare off the ottoman invaders so he killed the whole city and put their heads on a stake in front of his castle, so the vampire was born 
Yes Vlad the impaler, he was also known as Dracula isnt that right?