Recently I (stupidly) took my pickguard off my bass and took out the pickups and such just to see how it works and i really had no idea what i was doing i put it back together again but now my strings are really far from the neck higher up and really close lower down. is there something i could do at home to fix this with some screwdrivers or do i have to take it to a shop.

Since there really is no way for the action to suddenly adjust itself, I'm going to go out on a limb and say that when you were reassembling the bass, you accidently turned the bridge saddles (the things that the strings sit on) upside down...this would most definitely cause the strings to be dramatically higher.