I can't seem to figure it out.
Pressing F11 if in full screen mode, would bring everything back, but I believe that you are not in that mode.
Try this though:
You know you have Tools in the top right? Try dragging that part across and up, to see if the toolbar has just been moved.
Your toolbars are unlocked, so there is a chance this is the case, and you've simply moved them by mistake.
I hope this helps.