Reminder:
1。 Don't change your name to Feifei just to feel cool! Feifei is your legal name. If it is changed, it will be in big trouble, because it does not conform to the official registration. As for your own signature, it doesn't matter. You can use Chinese.
2。 Don't conform to foreigners, they won't teach before they teach. In fact, they like to call you by your Chinese name, and my former professors have always called me by my Chinese name, although my name may not even be good for China people.
To tell the truth, Feifei is not the correct English name either. Instead of this, it is better to use Feifei.