Thanks for reaching out @Vanessa_Evans and welcome to the Community Forum!
It seems you have enabled the option to receive email notifications when a task is added to the project. For that reason, when a form is submitted and the task is created, you receive a notification. You can manage your project notification clicking the Share icon in your project header and then accessing “Manage Members notifications”.
When you enable the notifications for “Tasks added”, you’ll be notified when tasks are created or added into the project. You can enable this option to other project members as well.
Our product team is working on a new feature that will send an email confirmation after a form submission. We hope to have news soon!
I hope this helps! Let me know if you have follow up questions.