Those are the few lessons I learnt from failure, what did you learn?
That was some common mistakes I've made too when I started trading. At least you learned your lesson at $100 some of the people I know lost thousands of dollars to learn that kind of lesson, one thing I can also say what mistake I've done before was trying the futures, when I started I don't exactly grasp its concept until later when I found out that if you lose it, you lose it. Unlike buying normal coins, you get a hold of that asset (no matter what the price) in futures, it's like placing bet, once you lose, you lose.
Everyone makes such common mistakes when starting trading and if someone can learn from those mistakes then only he can become a successful trader in the future. Sometimes we think trading is very easy but when we go into the practical world and lose a lot ourselves then we can realize how difficult trading is. When you start trading without being a trading expert then you will see that when you buy a coin then the price of that coin will keep decreasing and when you sell then the price will start increasing again. Although at that time it seems strange but when you become an expert then you will understand these things why this happens. I have also made many such mistakes but now I gradually try to keep myself away from these things as much as I can. And I try to be happy with very small profits.