Sometimes, people who have had a very bad experience in their waking life will have nightmares in which the attack (or abuse) keeps being repeated in dream after dream like a broken record. If this is your situation, fighting back in your dream can help. For some, these types of attacks will then virtually disappear within a few dreams. However, this doesnt seem to describe your dream.
Many Christians and non-Christians, as well, believe that there are evil spirits out there. They are probably right. Thus, it may be that you were attacked by such a monster. If there are evil spirits, then we should not be too surprised to learn that that are also friendly and even helpful spirits. One writer mentions what he calls the astral police.
http://kundalini-support.com/protect.html Apparently, we can get protection from these helpful spirits, but we have to ask. As written in the article, There are both light and dark energies in this universe and unfortunately, it seems that when a person goes through a protracted awakening and there are often overwhelming experiences to handle, alot of fear and negativity can be released. Which can attract negative forces. Thus, it is some of the most spiritual and sensitive types who attract these dark energies. Spiritual and sensitive? Sounds like many of the Christians that we know.
You wrote that you were trying to break through a window
. Here again the dream house that you are in can symbolize your physical body. Thus, this sounds like you are having another dream in which you are trying to escape your body.
The big teeth hint at another possibility. The mouth and, by extension, the teeth can be symbols of talking. Thus, it may be that some people are saying bad things about you. Or, less likely, you could be saying bad things about them.
Hope that some of these ideas were helpful.