OMG - using turbo tax I accidentally put in 4,111.82 in the fed tax withheld?

in the W2 portion of the software...instead of the 1,111.82 that is the real number. I put in 3,000 too much and my tax refund is saying I'll get back over 3,800.00 which I have NEVER gotten that much back in the past...problem is...I already efiled that return today. How do I catch this and change it? Will I be red flagged by the government? I really don't want to be brought on fraud charges I just made an oversight and didnt recheck my return like I should have. Please help!