Time is too fast to recognize it.I would combine this sentence with the previous one:Time goes by so fast that I didn't realize today is the last day of November.

It means that I have lived here for about 3months!(Did you move to a new place? Or are you staying for a period of time?)

There were so many things that happened..

I have to do something still.I still have something to do,

I will register for the Toefl test.

It will be on Dec 19th and I have to go to Houston to take a test..On December 19th I have to go to Houston to take the test.

I don't know how can I reach there whether my mom will give me a ride or someone help me or not.I don't know how I will get there; whether my mom will give me a ride, or someone else will take me.

I have know what I should do; but I don't know why, I don't can't concentrate on my studies.

Anyway, I hope that I will post 'I got it' like that..Anyway, I hope that after that day I will have a posting with the title: "I got it!"

I want to be good at using English and study~I want to study and use the English language well

It means that I have lived here for about 3month!This means that 3 months have passed since I left Korea to come to Texas.(I think it's best that you specify the locations because otherwise the reader might be distracted by the curiosity and may not pay as much attention to the rest of the writing.)