My exam was over

I revised it three times
I made it sure
No question was left unanswered

Still so much time was left
Few pages in my answer sheet were blank

I wrote one poem
I drew Tom and Jerry
I made few colourful patterns

Time was over
I submitted my sheet joyfully

When I was returned my answer sheet
I got cross on them
Many signs of question marks with red pen

I got above average marks
I showed my creative art

But I got unpleasant remark
"Should not I get reward?