Well, I'm impressed that you did it. Fellow stage fright sufferer. I understand.
Now, you had those reactions, but you know what, you survived, and are here to tell the tale. How did the audience react to your performance?
You don't need to sight read to perform. You probably should be able to keep pitch, but I've seen more than a few famous singers struggle with pitch and they still perform live. There's a lot they can do in the studio to clean you up, and there's a lot that patience and practice can do to help.
As for forgetting lyrics, write them down. You can put them on the floor. No one will even think twice about it.
And the last thing I can tell you is everyone feels what you felt. I have it on good authority. Your feelings were very normal.
Good luck! Can't wait to hear you!
Lynn