When I print my files what I see at the top of my computer screen is what physically prints last out of my printer? Does this matter?

No, actually it doesn’t. As long as the image is properly positioned on the film the way the data streams to the printer does not matter as long as the entire image is on the film and properly printed.

Some graphics programs have a setting in the print window to change the way data is printed. Adobe called it “Transverse”. This flips the image top to bottom on the page.