Do you still have access to receive email via your old email account? If so, you can recover access to your old AppleID:
https://iforgot.apple.com
This link will obviously help you to recover access to your new AppleID.
If you need to change your password, or update any element of your AppleID account (including a change to your email address), you should login to your online AppleID account at:
https://appleid.apple.com
As all of purchases and services are forever linked to your AppleID account - and cannot be transferred to another AppleID - you should endeavour to keep this account. Thus, should you need to change your email address, you should change it in your account - and NOT create an entirely new AppleID.
It’s also worth noting that you should setup rescue email addresses and trusted telephone numbers - again within your online AppleID account. These are used for account rescue should you become locked-out or if your primary email address is unavailable.
So, armed with this information, you can either try to resurrect your old AppleID, or reset your new AppleID.
I hope you find this information to be helpful - and that you manage to solve your problem.