Interesting... :)
This was very well written for your first English piece! Very very good!
I'll point out some mistakes for you - but really there weren't any horrible ones.

"Andrew did shut off the TV." - You could say "Andrew turned off the TV" or simply "Andrew shut off the TV."

"No, it would be a too sad coincidence" - Not sure what you want to say here...but the phrase "a too sad coincidence" isn't right. You could say "it would be a tragic coincidence"?

"Did you went outside when the door rang?" - Say "Did you go outside when the door rang?" :)

Anyways, you did a GREAT job, I hope you continue to practise your English. Have fun writing!