To view the last render, press Render in the top left-hand corner and select View Render. This can also be done by pressing F11.
If you still cannot see the render, at the top of the Blender Render window, click the small picture icon and make sure Render Result is selected.

Edit:
If you still don't see the proper render, check the top right corner for a drop-down menu marked with Slot.
Click on it and cycle through the different slots to check if your render is in one of the other slots.

Edit 2:
Found it! The problem was that you checked Sequencer by accident, so it wasn't actually rendering any images at all. I realized this when I reset the save location for the images and found all the renders were blank.
To fix the problem, head over to the Scene tab and open up Post Processing. Then, just uncheck Sequencer.
There's a great Q/A about troubleshooting blank renders here. It may be from the older UI but it still is of great help.
