Hello. We once played a ghost prank before 3 days to scare one of my friends. It worked well, as the prank was made a bit realistic. My friend was the one who played a key role in the prank. But after that the behaviour of him is changed drastically. He acts normal, but all of a sudden he shouts at us very abnormally. And also he is starting to laugh suddenly without any reason for several minutes. But he is not recogonisng that he is acting in such a way. We have no idea whether he is continuing the prank or he is mentally affected or is there something else. How can we move up with this? Help me please.