AWWWW that's such a sweet gift! how lucky for your mom :) <3
my first big purchase with my own money was a ps2 on my13th bday. I couldn't just outright buy it, NO, that would be too easy. my mom was super strict, and bc I already had a gamecube she said "no way in hell you're getting another console" (even with MY OWN MONEY). so I schemed, plotted, and planned. I babysat for like 3 months and saved up $150 or so, enough for the ps2. I then gave the money to my bff. she and her mom were super cool, they bought the ps2 for my bday and told my mom that her mom won it in a raffle at work. as an actual bday present, they got me DDR Extreme 2 which was the only game I wanted. IT WAS SO GREAT! mom didn't suspect a thing, and couldn't tell me "no" in front of my bff+bff's mom's face. we played DDR happily for years. in fact, I busted that bad boy out at my dorm a number of years, I've still got the moves.
sorry I had to get that all out, I was so proud of that, lol. I might tell my mom in like 10 years...tbh I'm still scared to even though I'm a grown ass adult.