Constant Null Reference Execptions from the Unity GUI (and hierarchy no longer working)

So lately, I've been getting TONS of random Null Reference exceptions, and they are NOT from my code. Sometimes it happens right before the in-editor player loads, causing it to stop playing. A few minutes ago, the Hierarchy tab decided it was going to break. Instead of saying "Hierarchy", it said "Failed to Load". I closed the tab, and then opened it again. Now, any attempt to go to the hierarchy tab causes all the tabs to freeze, unless I click on the top-left area of the scene window. Reverting the layout settings to default did not fix anything. Same problems.

The error that seems to be accociated with the hierarchy not working is this one:

 NullReferenceException: Object reference not set to an instance of an object
 A.c75a5672114a84bedb52785370c252279.c296bba64ea63714dbb0be4a019037936 (Int32 )
 A.c75a5672114a84bedb52785370c252279.c14579e49d278e67b120cbf471085391e (Int32 , Rect )
 UnityEditor.SceneHierarchyWindow.OnGUIAssetCallback (Int32 instanceID, Rect rect) (at C:/buildslave/unity/build/Editor/Mono/SceneHierarchyWindow.cs:458)
 UnityEditor.TreeView.DoItemGUI (UnityEditor.TreeViewItem item, Int32 row, Single rowWidth, Boolean hasFocus) (at C:/buildslave/unity/build/Editor/Mono/GUI/TreeView/TreeView.cs:441)
 UnityEditor.TreeView.IterateVisibleItems (Int32 firstRow, Int32 numVisibleRows, Single rowWidth, Boolean hasFocus) (at C:/buildslave/unity/build/Editor/Mono/GUI/TreeView/TreeView.cs:568)
 UnityEditor.TreeView.OnGUI (Rect rect, Int32 keyboardControlID) (at C:/buildslave/unity/build/Editor/Mono/GUI/TreeView/TreeView.cs:504)
 UnityEditor.SceneHierarchyWindow.DoTreeView (Single searchPathHeight) (at C:/buildslave/unity/build/Editor/Mono/SceneHierarchyWindow.cs:585)
 UnityEditor.SceneHierarchyWindow.OnGUI () (at C:/buildslave/unity/build/Editor/Mono/SceneHierarchyWindow.cs:399)
 System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)

A few other errors that randomly appear are:

SUCCEEDED(hr)

rc.right == m_GfxWindow->GetWidth() && rc.bottom == m_GfxWindow->GetHeight()

And I can assure you that these errors are not from my scripts.

EDIT Punching my computer seemed to have solved the problem. (It may have been a coincidence) but unity crashed at the same time I punched my computer. While I did lose some work, it also fixed the hierarchy.