Can somebody help me correct m work

The title is " Tell a story about learning experience that teaches you valuable lesson"
Here is my work:
In my learning career, I have been through many experiences. Some of the good experiences make me happy, bad ones teach me lessons. But the most memorable learning experience is the time when I almost missed my final examination at the university

I remembered that it was a Saturday morning and I was having a final examination reading test that week. I stayed up late night before the exam in order to hit the books. When the alarm went off at 7am, I got up as usual but somehow I lay down and slept again. When I opened my eyes, it was nearly 8:00am and the exam started at 8:10am. I knew that I was in big trouble because from my house to the university was about 7 kilometers and it took me half an hour to get there. But that was not the scariest thing. What I was afraid of most was that I wouldn’t be allowed to attend the exam because of arriving late. I took a risk and went to the university as fast as possible. It was 8:40am and I was 30minutes late. I rushed to the fourth floor where the examination took place. Far away, I could see the supervisor was walking around the hallway and he would never let me attend the examination but the one inside class might allow me to do the test. Luckily, the supervisor walked into the toilet. I knew that it was my only chance to survive. I quickly ran into class then explained to the supervisor that I had an accident . Somehow, she believed me and allowed me to do the test. Two weeks later, I passed the test with flying colors. It was a miracle and I couldn’t believe it really happened. From that situation I realize that I have to prepare for an exam sooner and let the day before the test be a rest day so I can be right on time.

The whole story is truly a miracle. From that experience I have learnt a lot of things and prevented it from happening again. I will remember in all of my learning career or maybe all of my life.