Hey, i have a Affinity Series Squier Strat and i soldered out the electronics to repaint the guitar and that went all fine, but...
today i soldered the electronics back in but when i put on a string and play through my amp i just hear a constant buzz with in the background something i think is my guitar's sound but that disappears once i touch a metal part on my guitar (string, bridge, knob, etc.)

on the picture of my guitar wiring i made (because i couldn't find one that matched with my guitar even on the fender website the squier affinity strat wiring they had was different to mine) the numbers 1, 2 & 3 are the places i soldered and (i think correctly) soldered them back, number 4 is a wire that suddenly was loose but i didn't solder it out, so i soldered it back where i thought it had to go because there was some solder on that piece of the pot and on the internet i found a picture of a strat wiring (not the same strat as mine) that showed that wire should go there.

now does someone know how i can fix my problem? did i solder something on the wrong place? or is everything in the correct place but didn't i solder it well enough? any help/feedback is welcome
Strat Wiring.jpg
It sounds like you have ground problem. Either you forgot a wire or you have a cold solder joint. This is a common problem. If your guitar has a set of humbucking pickups, try it on the humbucking setting and see if its still there. If so, its definately a grounding problem.
You will probably get yelled at to use the wiring questions thread, but w/e.

You have wire 4 attached correctly. What you are doing when you touch something metal on the guitar is grounding it, meaning that you have a ground wire not connected somewhere. Can you hear the guitar tone when it is played? If so then check your solders: you may have made a cold solder. Use a continuity tester to check them.
Double check the grounds. Sounds like something isn't right on the ground side of things. Make sure it's the guitar and not a cord. Check to make sure everything is contacting correctly in the jack too.
in the background i can hear my guitar sound vaguely, but if i touch it that's gone and a lot of buzz is gone too. thanks for the help and what is cold solder exactly?
A non-conductive join. It comes from not heating it enough when applying the solder.

It has something to do with a layer of resin blocking the current if I recall correctly. Usually just reheating it will fix it.
i've now plugged in the jack and a headphone to my amp and i hear a buzz, even if i touch the metal but the buzz gets a lot softer if i touch my laptop that's connected to it's power cable at the same time