requesting computer help again

I have and epson R300 printer and every now and then it goes haywire.
I asked the printer to print some web pages last night (tablesaw blade holder) , there were 5 pages and I requested the printer to print greyscale to avoid all the colour inks being used on its fancy web page.
It kept refusing to print pages 2 to 5 and I did nozzle print checks also refused to print and requested word to print some letters from a file.

Switched PC off and printer, No luck on restart.
Went to bed in a huff:;
Switched the printer on this morning and it started churning everything out.:doh:
The web pages the information was in gobbledebook but the prints from Word was OK.
I know the printer is working OK again but what is going on?