Can you correct these sentences?

Last Wednesday, it was the third time I tried taking giving a trial lesson.

Finally, I was able to manage the time. (At The first time, I couldn't keep continue teaching for a full 50 minutes, and the second time, I did it too much exceeded the time.)

Being punctual was the most important goal, so I'm really happy to have achieved it on the third attempt.

However, I explained some parts I explained in too much of a rush, especially grammar.

I had no room in my mind...???

 
I also thought I have to be not only just a teacher, but also a student at the same time.

I have to feel sense and observe more, how students feel when they are being taught.

In 3 weeks time later, I'll take a trial lesson again.

It's the last time doing a trial lesson this spring semester.

I'll think and prepare for it as much as possible.