I’m 18 and have been playing for 4 years
Hate to say it but you are a youngster and with only 4 years of playing I wouldn't be looking to set the world on fire.
Playing bass should be fun first of all, one should be able hear bass in songs they listen to. Believe me many folks can't pic out the bass in almost any song.
I've been playing for well over 5 decades, and still love it. Never thought I'd make a living doing it and I don't. But I sure have had a lot of fun, and met some real interesting people. But I have always played locally, and have a good reputation as a decent player.
Never went to school to study music and play by ear. I hold my own with most all the locals around. Been on stages doing intro shows with B.B.King, Bobby Blue Bland, James Cotton, Johnny Winter, Jimmy Vaughn, Delbert McClinton, CCR, Miami Sound Machine, and even Joe Bonamassa. Been on trips, even to Cancun to do a gig with my band. But I was playin for many more years than 4.
I do understand your frustration, I guess it happens to us all from time to time. Just need to push through that. But the main thing is, you play bass because you like it and hear bass in your head. And that it is fun.
Tempo all comes in due time, get a metronome. Make sure you tap your foot. Even when just listening to music tap on something in time. It builds up physical memory.
All I can say is if you can't have fun, might as well get a triangle or a harmonica. Sure a lot less to tote around.