Problems after Open Unity 5 project with Unity 4

I accidentally opend a unity 5.x project with Unity 4.6, then Unity started an attemp to migrate that project. Trying to avoid this, I killed the Unity 4 process, opened my project in Unity 5 hoping nothing changed. At first everything seemed to be OK (code, objects, source files), but as I built my game for Android as always did, some scripts are not working, not errors shown but game is not behaving the same. I ran my project for pc, and it works perfect, but it is not the same for Android. What should I do to correct the problem? What would be the problem?

You should restore the project from your backup or source control.

Try this:

  1. Rename the “Library” folder in your project (ex.: “Library_backup”)
  2. Open your project in the version of Unity you want to use the project with (all your assets will re-import, and the Library folder will be re-built)
  3. Correct any code errors that may have appeared in the console due to previous upgrade to Unity 5
  4. Verify that your game works properly
  5. Optionally delete the previous Library folder you’ve renamed in step 1

I solved my problem, I realized all my tags disappeared as a result of my initial mistake, so I wrote all tags I’m using, and all is working perfectly. Thanks guys.
What is weird is, as I was testing on Unity, no error was shown, everything seemed to be ok, that was confusing me.