This looks like a sentence from a song. Song lyrics are often can't be 'interpreted' normally, however, probably we can at least understand what the writer wants to say. From the song, this sounds a 'depressing song'

From that song, it can mean anything actually. But I've got a feeling that it means kind like you betray your friends or colleagues (sold out your friend for something..) and the writer said in previous sentence:
I know the feelings away, uh = he knows that (actually he doesn't really want to do it thus the feelings are off/away)

I will sell out my shit some more, ah (so he will lie/ more with 'some shit'.. shit can mean anything from something cool to tease or try to deceive (someone) or just an angry shout..
Let's see:
From Webster:
"sell out verb
Definition of sell out (Entry 2 of 2)
transitive verb
1 : to sell the goods of (a debtor) in order to satisfy creditors
2 : to sell security or commodity holdings of usually to satisfy an uncovered margin
3a : to sell all the available tickets for sold out the concert
b : to sell all of the merchandise was quickly sold out
intransitive verb
1 : to dispose of one's goods by sale especially : to sell one's business
2 : to betray one's cause or associates especially for personal gain
3 : to be or achieve a sellout
For the best interpretation of the song lyric, you can consult the songwriter:
Songwriters: Carlton Mays / Marius Listhrop