Over the past few months, I've made so many incomplete songs. I'll think up a good melody in my head, play it on guitar... Then get stuck. I can't figure out the backing tracks for it. Sure, it works if I just try, but that takes a lot of time.

Should I just start learning theory? I don't know much of it.
thats why most sucessfull artists take years to push out an album. Lots of ideas but it takes time to put them all together

Epi Les Paul Std w/Duncans
Cry Baby From Hell
Marshall JH-1
EHX Metal Muff
MXR EVH Phase 90
Carl Martin Classic Chorus
EHX #1 Echo
Ibanez LU-20
Dunlop DCB-10
Crate V50112
Tascam US144

What do you mean it works better if you try?

You should be trying to write the best music you can anyway. Right?!

But knowing theory never held anyone back. I'd advise you to learn some.
I deeply regret the 6661 in my username. Siiiigh. Damn you, 14 year old me, you edgy little bastard.
Yes Theory!

dude theory has helped me soo much when it comes to writing these days, like if you got a melody and know the key you can figure out multiple chord progressions to fit it, then start throwing in the 7ths in theres and use diminished and augmented chords and Secondary chords, make your music harmonies and give it dissonace, dude theres a reason the beatles were so damn good, they knew what they were doin and they actually tried.

You'll make your music 10x better if you actually knew what you were doin, no offense just trust me Im livin it
learning theory can't possibly make it any more difficult. so on that note, do it, learn theory.
If you are blessed with a LOT of musical experience, say 10 years or so, then the music theory and composition will come to you naturally, like it did to me. But if not, which is probably more likely, then taking music theory will help TREMENDOUSLY in composing music.
imo, don't try so hard, and don't be too meticulous
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Quote by kirbix
Sure, it works if I just try, but that takes a lot of time.

Quote by Leonard Cohen
Well, things come so damn slow. Things come and they come and it’s a tollgate, and they’re particularly asking for something that you can’t manage.

They say, "We got the goods here. What do you got to pay?" Well, I’ve got my intelligence, I’ve got a mind. "No, we don’t want that." I've got my whole training as a poet. "No, we don’t want that." I’ve got some licks, I’ve got some skills with my fingers on the guitar. "No, we don’t want that either." Well, I’ve got a broken heart. "No, we don’t want that." I’ve got a pretty girlfriend. "No, we don’t want that." I’ve got sexual desire. "No, we don’t want that. I’ve got a whole lot of things and the tollgate keeper says, "That’s not going to get it. We want you in a condition that you are not accustomed to. And that you yourself cannot name. We want you in a condition of receptivity that you cannot produce by yourself." How are you going to come up with that?

Quote by Ed O'Brien
“It’s not genius. It’s just that if you want something good to come out of something, you have to put in a lot of effort. That involves a lot of hard work, and a lot of blood, sweat and tears sometimes.”