Haunted!?? help!? confused !?

Okay so I just moved into the house my aunt left me in her will. It is about 150 years old, but the original house has been remodeled and built around, like the original bathroom is now the outside patio, anyways I saw wat looked like as a little girl walking up stairs that weren't there, also I saw a shadow standing at my bedroom window from the outside, this was upstairs and there's no ledge. I smell smoke and black a milds(you know the smell?) The scariest thing that happened to me was about a month into the house I was sleeping and had a weird nightmare about someone hiding out in the attic waiting for me to fall asleep so he could kill me, I woke up and heard footsteps upstairs, me being a coward called my boyfriend to come over immeditly to check it out with me, when he arrived I was hystarical. We went up and saw the window open and a freshly smoked cigg. Could they have warned me? Is this a haunting??? Nothing like this happened in my life before, what should I do?