How can I send a form from my old account that I shared to my new account I just started?

You can add your new account as sub account user of your old account and share your form. 

How to Share Forms with a Sub-account User

If you want to move the form to your new account, we can do it for you. Just provide us ID of the form and username of account to which you want that form is mode to, like it is described inside of this guide as option 1:

How to transfer or share forms and data with another account 

You can also check option 3 of the same guide and do it yourself.

Hope this will help. Let us know if you need further assistance.