The basic umbrella genres in include anything that can fall under the rock category, such as psychedelic, metal, punk, and so forth. Country catches country of course with it varied sub genres such as western, western swing, bluegrass, and so forth. Which are basically your two primary genres. Once you start adding others such as Symphonic, Opera, Jazz, and some of the other main genre headers, then you start to truly become diversified, or leaning towards the eclectic, but to be an eclectic, requires the ability to listen and actually enjoy music from multiple genes. You have though made a start, in that direction. But please understand that there is what is termed in country as the traditional sound, and the modern country sound which is more a pop sound than true country. A traditionalist will enjoy more the sound of the traditional form of a music than the modern version. This goes for all genres of music.
Your age could be a factor in things, but also you could be finding that by opening up a little more, there are other types of music that are enjoyable, and pleasing to your ears, to listen to. If I could give just some advice musically, that is don't accept the stereo types given to a genre of music. These are used commonly by people who want to, or feel the need to use them to either try to put people in their place, and make themselves feel better about themselves Also for some it's a way to show, that somehow they are so much more superior, in what they listen to. Even if it's just one genre of music. Sometimes it's these very same who claim how open minded to things they are yet, in sad truth they are closed minded, and will still go to great lengths to prove otherwise. The next is not to jump to far back into a genre otherwise it could prove a point of becoming turned of to a genre of music. Instead of trying to immerse yourself in what is out there, use where you're at, and work at it slowly and move backwards somewhat, and listen from new to old. In short don't jump from now say Slipnot to the Beatles, or from say Taylor Swift to Loretta Lynn. Ease into it. Find something similar to what you like, and then have someone recommend something that would sound close to it, listen to that and keep building on the foundation, you're creating.
Although it could be possible to make the jump from new to old, usually it doesn't work out as well. You're young yet, and have the time to develop a varied taste in music. It's like eating an apple, it's easy when you do it a bite at a time. Yet try to swallow it all at once and you will choke on it.