Overstayed on F Visa for 19 days

Hi, I'm holding a Thai passport and I'm currently at student here. My situation is quite complicated.

I first entered as a tourist and then I applied for two language courses (August 2013 - February 2014) at one of the university in Beijing. Right after I arrived here, I have asked university to assist me on applying student X. For some reason, it is not student X instead it is F and has two time entries.

Unfortunately, I misunderstood the regulations as I went travel to other country and I came back. I did not realize that once I came back I can only stay for 30days. As of now, I have overstayed for 19 days and they considered my F has already expired.

My question is What process would I go through and Would I be able to renew it until February next year? and if I want to further study next semester course (February - July 2014) are there any difficulties applying for it?

Thank you.