All of my Apple Apps don't work

After upgrading to El Captain, my Mail, Safari, iTunes store, and App store do not work.

Safari won't connect to the Internet. My Mail app cannot connect to my accounts. iTunes works and I can listen to music, but I cannot connect to iTunes store. Also my App store won't connect. Pretty much all apple apps I have do not work anymore.

Did my upgrade not download properly? What should I do? I am not dying, but it is annoying that nothing works.