Spiders in my dreams?

I regularly have really vivid dreams of spiders, they are so vivid i wake up in fear and have to switch the light on to search for the spider i have been dreaming about, only to realise it was a dream and that its not actually there. I need to know what this means, i don't wake up in fear about anything else, and i'm calm and controlled if i do actually have to handle a spider in real life, i want to know what spiders symbolise properly, please don't copy and paste a "dream dictionary" paragraph or anything, i've looked at them all and its not enough to know that they "symbolise prosperity" ar anything like that. These dreams are starting to concern me now that they would genuinely wake me up out of a sleep!