Is it possible to exchange a mattress you just bought 2 weeks ago for a bigger one?
I bought a queen size mattress from The Original Mattress Factory about 2 weeks ago. The mattress is very comfortable, however, i would prefer a King size. Do you think they will take it back so i can upgrade to a larger size? Is there anyone out there who has done this before and was successful?

Don’t hesitate to call the store. Because you want an upgrade you shouldn’t have a problem. It really is contingent on the store.
You should call up The Original Mattress Factory. It depends on their own company’s policy and the condition of the mattress. Some mattress stores do have a 30-day money back guarantee.