Long story very short, aside from reps for the weekend, I had a gold tone Seiko Kinetic at your age when I knew zilch about watches and was in it for the look. Flipped it and downgraded to a dress gold, fashion Armani, which I flipped as well when the crappy leather band gave me a rash - sold it to a jeweller's kid who put it on a very nice gold done bracelet.
I regretted selling the Seiko later. Its not a big issue to have a nice gen watch at your age (and depending on budget, I'd say get a Seiko if you want something which you can beat up forever, jury is still out on the longevity but a step up might be a Steinhart, either will serve you well), but be real about what you're buying and why at 17. You need a daily wearer which is actually water resistant (shock and horror, most reps aren't) and which won't be finicky on the service front. I had a secondhand Seiko which got a service after years and years of abuse strapped to my arm on a Zulu. Can't say the same for reps.
If you want to get something to commemorate an event like this (and congrats, whether this is the start of another journey of study or if this is game over for school and on with some real world stuff) go gen.