@Caitlin Worrell
You do have options.
I've heard of people appealing with their lender - have you tried this?
If the bank gives clearance you can discuss the report with the appraiser.
You can find a member of the appraisal institute and ask for a review of the appraisal.
You can prepare for a new appraisal by looking at appraiser-selected comps - some appraisers will do a comprehensive search for comparables, and then discuss them with you.
You can order your own appraisal.
I know it's infuriating. All the new guidelines have more than doubled appraisers' cost of doing business while simultaneously reducing fees. They have to avoid any hint that a buyer, seller, lender, owner or any other party had an influence on their opinion of value. Then they have to field calls all day, write responses, and new reports. It's pretty typical for appraisers to work 12-18 hour days. I did. Maybe your appraiser is overwhelmed and made a mistake.
Talk to your bank about options. Appeal if you can. Maybe have an attorney review the appraisal if you feel you've been damaged - appraisers do carry E&O insurance. Either way the market seems like it's accelerating like in 2004-2006, so maybe just apply again.
Good luck!