I like the repetitive rhythm guitar running through the piece and feel you should have made more of it, ie a little louder in the mix…it has a nice feel about it, I think the lead guitar is a little to “up” in the mix,
a nice “cruising” instrumental 
everyone uses the same old chord structures and as far as I know you can’t hold intellectual copyright of a chord sequence.
unless it’s “Wild thing” or “You really got me” nobody could use them again could they. 
it’s the song on top of the chord structure that counts.
and i don’t think you’ve accidentally used anyone else’s tune.
Good instrumental with a good feel…
best, Kevin