Could someone interpret this weird dream that I had?
I dreamt that I was in an unknown house (that looked as if it were new) that caught on fire; my grandmother and my sister was with me. So we ran outside, but there were these things raining down from the sky that were like bombs , i tried to run as fast as i can, and my sister and grandmother were lagging behind, but i was out of breath, so I couldn't even call me, I eventually tripped, and so I tried to duck, sort of bracing for impact, after awhile it was over, and when I got up and looked back, where my sister and grandmother was, was a huge pile blazing with fire (In my dream I interpreted as if they'd...died...).

Interestingly enough, my grandmother is dead, while my sister is alive...so....
and throughout the dream, I had a feeling of dread...
the dream was actually split into three parts, but the other two are more vague and non-nonsensical and are more fantasy-like.....

The dream reflects a situation in which you are using a mental attitude or way of thinking that may be new to you but perhaps not yet one you are perfectly comfortable with. (in an unknown house that looked as if it were new) There might be a lot of passion pertaining to the new way of thinking (fire) but the fire also indicates some destructive illogical thinking is being done.

There is an aspect of yourself (the grandmother and sister) that is providing the emotional support for a new way of thinking. Yet the scene is suggesting that you would be making fast progress when leaving this way of thinking. (we ran outside) Your emotions/feelings however, are slowing you down in this regard. (my sister and grandmother were lagging behind). You cannot call to/for these feelings, meaning that you cannot express a need for this emotional support because you cannot draw enough upon higher consciousness or intelligence to do so. (was out of breath, so I couldn't even call them) You are tripping yourself up – doing something to hinder your own progress. [Here this might be trying to preserve a feeling or idea you really care about?] In retrospect (looked back) you may come to realize that illumination or enlightenment comes with the termination of a feeling/idea you really care about. (a huge pile blazing with fire ... they’d died)        
     
Something appears to be impeding your progress out of an illogical, destructive situation and way of thinking. (these things raining down from the sky .. like bombs) Bombs can represent a startling idea, one that is devastatingly destructive and comes usually unexpectedly as a shock. Because these things are described as ‘raining down’, something that could seem like a shock with terrible consequences may be seen in your mind as a blessing.

Your grandmother would refer to a great or grand belief you have. In this case it is one you could give honour to in your mind but is not of any use in physical reality. (as she is dead) As she is the elder in the family, such a belief could be regarded as governing your emotions in this situation.