Weak wifi signal after home button change, tried everything!

I recently changed the home button on my iphone 4. after reassembling it I noticed my wifi signal was extremely poor, so i searched the forums and saw that it might be the screw in the antenna so i tightened it, but it didn't work.. I checked to see if the tiny metal piece that connects the frame to the motherboard was there, and it was. So thinking it might be the antenna i ordered a completely new one and put it in with the new tiny metal piece as well, but it still didn't work!

I don't know if there is anything more i can try.

I even tried connecting the golden circle on the motherboard directly to the other golden thing slightly left from it which connects to the frame, didn't work either. so if there is anything more i can try, please tell me.