This is a day full of regrets. I lost 400 dollars by neglectig to pay last Friday for my flight booking to New York. When I did it today, the cost, the travel agency gave me last Friday, rose by more than 400 dollars. Oh my, I could have bought a new laptop with that difference. I had no choice but to pay the current cost otherwise if I fail again, the cost might be more than the curent amount I paid. I only had to scratch my head and learn a lesson out of it.