Hey, I'm a bit of a bass noob, only been playing for 3 months. I've learned to play many songs from artists like STP, Pearl Jam, RHCP, Fugazi, etc. However, I feel that I'm stuck and can't progress right now. Besides songs, what should I practice?
If you don't know what to learn, maybe see about getting a few lessons so you have someone to guide you for a bit? A good teacher should give you stuff to learn rather than waiting on you to bring something to every lesson.
Founder of Jaco society

[22:08:23] <Confusius> I wish I was a bassist
[22:08:26] <Confusius> you fuckers look cool

Want to know how to play bass in jazz? Read this.
Try a different genre, expand your musical horizons. I'm sure you'll find some new influences then.