Before you closed on this home, were you given a time period for due diligence? Typically, before a buyer signs closing documents, there is a time period of a few weeks where the buyer can have inspections done, research the neighborhood, schools, commute to work, etc. During this period of time, the buyer can back out or cancel the transaction using one of the contingencies in the contract. Typically, once you close and the title or deed transfers into your name, anything that happens after that day is your responsibility.
As Solomon said, you can sell your home the day after you close. There is no wait period. However, in most cases it takes a period of about 3 - 5 years for a new owner to gain equity in their home. If you sell before the 3 year time frame, you will need to pay cash to sell your home. Buyers will see what you paid for your home and will offer less than what you paid.