HELP WITH WORD PRETTY PLEASE!!

Hi,

I've recently created a document in word that was supposed to be handed in to uni a couple of week back.
when i right clik the document and go to properties it shows the date created and date modified. The creation date is fine, the modified date is the problem. Because i found some mistakes with the grammer that i corrected the modified date has now changed to todays date. That isnt a problem again because i changed the date and time on the pc to roll back the modified date.
The problem now is that the uni's in uk use software that tell you if you been copying your work etc... i was wondering can they tell if the date on the document has been back dated?

Many Thanks