I don't think every problem we face requires a mental health professional or doctor, I think some things we're capable of handling using our minds. The OP has already stated that he has little interests, that has absolutely zero to do with depression. It's just that he has no interests (beside video games).
Still, its worth looking into. Its better to get it taken care of early before it gets entrenched. And depression can be a reason for having no interests, because it can mean a lack of motivation to seek interests. Depression also isn't just black and white, there are vary degrees and everyone experiences it in a slightly or extremely different way. Most if not all mental disorders are a spectrum, with varying degrees of severity.
OT: OP, at least get it checked out with your doctor. I think there are also psychologist you can talk to online for free who can help determine if you should really go see a therapist or not.