Hi,
Try out this
1. You can add two actions to the the button rules, one is to submit data to sharepoint and second action sends email.
Adding rules
1. Double click on button to open button properties dialog
2. Click on rules button in the button properties dialog.
3. Click on add button.
4. Click on add action button
5. Select "Submit using dataconnection"
6. Select sharepoint submit dataconnection.
7. Follow 5-6 steps and select "Email" dataconnection instead of Sharepoint connection.
8. Click ok to set the rules.
Hope this help You
Thank You,