I got much more than expected for my return. I'm worried about a audit.

[FaithY]

Since you got much more than you expected as a refund on your tax return, I suggest comparing your 2016 tax return to your 2017 tax return line by line to see the differences. Start at line 1 and work your way through the tax return. Once you have found the differences, you can look into them further to see if there is something wrong. 

Don't be worried about an audit. If you are audited, you will have an opportunity to provide documentation to support your income, deductions, and credits. If you don't want to represent yourself during the audit, you can always find a qualified professional to speak to the IRS or your State on your behalf.