Hi, I can relate. Did a lot of jamming in the past and am into trying to produce some music. Sort of reaggaestep/dubstep.

One thing that helps me with inspo is listening to other peoples music. Music you really like. Somehow it gives me the feeling of 'yeah, I want to make something awesome too!'.

And, what I do if it starts sounding too much like an existing song, is to just change the chords or notes or chord progression to something else you like but retain the vibe you want as well. A lot of songs sound similar to each other, I mean entire genres sound similar. As long as you know you're not copying or plagiarizing anything, it's okay. It's music!

Enjoy.