Could somebody check my writing? :D please

I'm sorry I have not written for so long but I had an accident. Last Friday I decided to ride a bike. It was very warm and I needed some fresh air. I took my helmet and some protectors to knees. I thought it would be good protect from contusions.
I wanted to ride to my girlfriend and give her a letter, which I had written for her. So, I rode. I was riding really fast, suddenly I crashed in the wall becasue on the street was lying the nail and I didn't see it. I remember only one man who took phone and called ambulance. I needed real help. The ambulance arrived and took me to hospital.
I got serious injuries, broken leg and concussion of the brain. I was lying in hospital for one week.
I think if city council hired some group of street cleaners, it would reduce the number of accident because on the street is lying many dirt which are dangerous.
That's all for now. I hope to hear from you soon.