This wasn't so good.
You need to work getting "bigger" rhymes, by bigger I don't mean really big, just some more rhymes and so on so it looks like it's more complex and stuff

Really hard to explain it..
To be honest, your second verse was just wack.
Try avoiding using the same word at the end of every line.
Like you did here:
"your not my brother, your momma should of used a rubber
back then again you nasty fuck came from a used rubber"
You didn't have that many rhymes, next time try to rhyme a bit more..
It's good that you're trying.
Keep it up
PS: No hate, I'm just trying to help..