Just because she masturbates doesn't mean she'll lay eggs. Just remove the toys, bowls, perches, etc that she uses. Then put her on hormone reduction techniques. They can be found in the sticky library under the breeding section.
thanks for the replies. she is my first tiel, and her and archie aren't even 12 months old yet so all these little teenage habits are new to me. i haven't seen her do it since, so hopefully she'll stop. it was a horrible site to see, hahaha. i had to shield my eyes for a second.