What does my dream with spiders means?

Last night I was dreaming that I was on the 3rd floor of our school, I was near my clroom then someone ask me to go to the lower ground. I obeyed but I was startled by a spider (more like a tarantula) on a step of the stairs. I quickly run for the other flight of stairs but I saw more spiders there so I quickly turn around and saw red and transparent spiders. I became frightened so I checked the Audio-Visual room for Spiders. I saw one transparent spider sneaking past me and almost entering the Audio Visual Room and I stepped on it. I woke up after it. I have a slight Arachnophobia and even after waking up I felt slight chilly about my dream. What does my Dream means?