If you will get a copy of the book "Hostage to the Devil" by Malachi Martin it will explain what happened to you, what to do about it, and also that you are in no danger now because all these things can be controlled through Christ.
That book is an absolute pain to get through. Malachi is a very controversial ex priest and still so catholic in his beliefs it would take an extremely dedicated catholic to follow his beliefs. But if you have the patience, it would be very worthwhile to hear what he has to say. For instance, what you came across is very real, and it can only be handled through Christ. To handle it personally is very dangerous. It is a long book and he has a lot to say about it from personal experience as an exorcism. Another book to understand is "People of the Lie" by a man who was a leading psychologist.
Demons who work to possess are in our world today more than ever because of the life we all lead, and the way the church is headed regarding how they regard law.