Major mistake on taxes?

When doing our 2009 taxes, I made a major error. I utilized a deduction which we were not eligible for (private mortgage insurance). We don't even have private mortgage insurance. I realize this was a colossal mistake on my part, but it was an honest mistake. I was advised it was something else altogether. Reviewing our tax return for something else brought the error to light. We received our refund already. I know I need to file amended returns and repay the funds to the IRS and plan on doing this ASAP (we haven't spent the money yet). I can have it in prior to April 15th, which is good.

My question is, will this stupidity on my part red-flag us for audits or questioning on this tax return or future returns? I guess I'm just generally concerned how the IRS will view this. It was really a stupid mistake.