Welcome, I am Cory.
Unfortunately, there is not a way to recall the email you have just sent.Sending an email is kind of like mailing a first class letter at the post office. Once it is on it's way, you are not able to stop the process.One thing you can try - is sending the person 20 emails that are blank, with the same subject. When they open the first few, they may just delete the rest thinking it was an error. (This possibly works if they have not opened the email yet.)
If this is something that has happened to you more than once, you may want to use a feature in Gmail for future emails.You can create a Gmail account here. - https://accounts.google.com/SignUpThe feature is called 'Undo Send'If you create and account and click https://mail.google.com/mail/?shva=1#settings/labs to go to the labs section.Scroll down to Undo Send, Enable, then click on Save Changes.Next time you send an email you will see a message at the top to undo/cancel.I believe it lasts about 20-30 seconds after you send the message.
I apologize outcome, but all I am able to do is inform you.If you have any questions, please reply and I will assist you.
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