What is the meaning of this dream?

i had a dream last night and it is about that i was in my house and i was sleeping there in my room when suddenly someone knock on my door many times and i didnt open it, i was afraid to open it because there someone outside there who is a bad guy, he tried to knock again and for my curiosity i open it a little and i saw nothing there. then when i close it again, i heard another one who is knocking at my door, then when i open it i saw this 3 boys who is young and the one who knocks on my door has a knife on his hand like he was trying to kill me but when i face him at my door, they ran so fast outside and i ran to them to have a fight and i shouted at them outside my house, i notice them like i know them so much in my dream and when i get back to my house i saw my mom there and she was worried so much to me and she touch my face and said oh my god donna, your not safe here in your house they are trying to kill you! i stare at her because i remember that my mom was died 2 years ago.. and i got curious on here because in my dream she was very worried and scared to me for what was happening.. i cannot interpret this, can someone help me to understand this?