So, just to be 100% sure... you forgot the e-mail address you used to have, so now you can't access your account, right?
(Sorry, I'm slow in the morning)
Anyway, if that's the case, you will need to contact EA Help. Before you contact them, prepare some information that will be necessary for verification that the account is yours:
A serial number from one of your games (if possible), it's the easiest identifier that can be used to locate an account. If you do not have a serial number available your Gamertag, PSN ID, or Character Names from online games will have to suffice. Generally, the more you can provide, the better.
The email address you would like to be contacted at
Your actual date of birth
The date of birth used to set up your account
In order to contact EA Advisor you will have to follow these steps:
1 Click on the following link: https://help.ea.com/contact-us
2 Make sure that you're signed in and select your country by clicking on the flag in top left corner and picking your country from the list.
3 Enter the name of your game (in your case it will be Origin) and click Next
4 Select the platform you play on and click Next
5 Select the topic (for you it will be Manage my Account) and describe the issue
6 Select a contact option. Availability of contact options depends on hour and day of the week.
That's all that can really be done.