icon and activities view are extremely big

When I open the Activities icon are big and can not access to the softwares. It seem that the shell can fix my screen resolution.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: gnome-shell 3.12.2-0ubuntu0~trusty2 [origin: LP-PPA-gnome3-team-gnome3-staging]
ProcVersionSignature: Ubuntu 3.16.0-29.39~14.04.1-generic 3.16.7-ckt2
Uname: Linux 3.16.0-29-generic i686
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: i386
CurrentDesktop: GNOME
Date: Fri Jan 30 07:50:18 2015
DisplayManager: lightdm
GsettingsChanges:
 b'org.gnome.desktop.interface' b'cursor-theme' b"'DMZ-Black'"
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
 b'org.gnome.desktop.interface' b'icon-theme' b"'Moka'"
 b'org.gnome.desktop.interface' b'gtk-theme' b"'Moka'"
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
InstallationDate: Installed on 2012-09-03 (878 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423)
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)
XsessionLog:
 openConnection: connect: Aucun fichier ou dossier de ce type
 cannot connect to brltty at :0
 Script for ibus started at run_im.
 init: Le processus gpg-agent post-stop (3884) a été tué par le signal TERM