Well, first WHY did you have the home appraised? Were you considering a mortgage refinance? Was it for insurance purposes? Are you planning to list it? Different reasons could account for different appraisals. For example, a realtor might want you to be more reasonable on a listing price. If a bank or mortgage lender really wants to justify a loan, they might hire an appraiser who they know is generous. Or there could be a reason outside your home — perhaps a changing neighborhood, or foreclosures down the block.
Depending on the reason, you might have a second appraisal done immediately and if there is a significant difference, you could average them — or ask a lender to discard a lowball appraisal.