In short, dreams are symbolic expressions of your feelings about your waking life. The meaning of the symbols in your dream should help shed light on the meaning of your dream:
room:
dreamdoctor.com/dream-dictionary/definitions/room.html
baby:
dreamdoctor.com/dream-dictionary/definitions/baby.html
attacked:
dreamdoctor.com/dream-dictionary/definitions/attacked.html
demon:
dreamdoctor.com/dream-dictionary/definitions/demon.html
Without knowing the waking life circumstances that generated your dream, it's hard to say precisely who the old man is... or the baby, but it's clearly about something in your life that has you very concerned. Feelings in dreams are never disguised, so how you felt IN the dream is how you feel about its subject in your waking life. The dream could be about a new project or relationship in your life that you fear will be "taken away from you" by an "old demon" that haunts you, which could be anything from an addiction and depression to an "older" person in your life. Often the more obtuse the dream, the more out of touch you are with your feelings about its subject. This is often self-protective, because those feelings so painful, scary and/or raw.
If you wouldn't mind sharing some details about your personal life at the time of the dream, it would be easier for all of us to help you connect the dots. Sometimes, it's easier for an outsider to see it than the dreamer. That being said, only the dreamer can validate the true meaning of his or her dream.
I hope that helps! Good luck.
PS There's no need to freak out about your dreams, because they are about your feelings, not the future. Understanding the meaning of your dreams will help you understand your feelings about the really important issues in your life. Knowing that, you'll be able to make better informed decisions... and that's a good thing.