I agree with Brandon. If you are having buyers remorse you need to think it through before loosing your earnest money. If your employment has changed then the conditions of your pre-approval have changed and you are no longer able to qualify. That would be the "honest" way out.

Simple ... Call your attorney and your loan officer. If your mortgage company issued a commitment, with a clear to close you may be in breech of the contract and the seller may get your earnest money.

I never understand how someone "can't" afford a home all of a sudden. What did you do in order to change your financial situation? Or are you just getting cold feet?