Ur chinese is good, but I revised as below to be more natural.
(you could also correct my below english comments, ha)
Chinese Intro:
我叫福佩芝。
我是美国人。,我十九岁。
It is noticed that many beginners tend to make each sentence as one Sentence with a full stop, virtually it could be a clause which we use comma to seperate.
我的生日是十一月三十号。
我是大学生。,我学习汉语和日语。
In case two clauses have the same subject, typically we could omit the second one.
很高兴认识你~
Chinese Intro:
我叫福佩芝。