Hello Diana

First of all, don't be panic.

You must have provided your email during registration process. You must have got an email with your registration number. If you don't get or you are unable to get , then you can send a mail to NTA customer service  or you may call them, the phone number you can get from anywhere , They will surely listen your problem and help you.

Hello Aspirant,

I'll recommend you to  visit the email Id that you provided during registration process.NTA must have sent you an email with registration number . Also you can check your text messages in your mobile phone.  If you are still unable to find it anywhere then i  will suggest you to get in touch with the NTA customer service by emailing or by calling them. They will help you in  resolving your problem .Talk to the customers and brief them your problem. They will guide you for sure.

Good Luck