Actually, I have faced this situation and at that time I was not aware of this important feature of gmail. At the same time searched for this and got the solution.
This is not any hidden trick or third party application, it’s just a gmail’s feature, which I’m going to share with you today.
There are many other gmail’s important features, just check this article- Unknown Gmail’s Useful Features : You Must Know
Learn: How to Undo Sent email’s in Gmail
Follow the below steps:
Step 1. Login in to your gmail account by using your user name and passward
Step 2. click the gear icon on the top right of the gmail and select settings option from the drop down list box.
Step 3. Now click on Labs tab in the settings page.
Step 4. Find undo send option and enable it.
That’s it. Now it’s your turn to apply this gmail’s feature and be safe while sending emails to anyone.
Read This: How To Increase RAM in Android
Change the Delay Time on Gmail’s Undo Send
The default time for undo buffering is 10 second, but if you want to increase or decrease its interval, then you can increase it up to 30 seconds and decrease to 5 seconds.