No, you should not normally join two sentences with a repeated subject using only a comma. If you believe there may be confusion as to the subject of the latter, you can instead use a semicolon.
Semicolons can be used to join two related sentences, so long as both can stand on their own. If it would be improper to write two sentences separated by a period, it is improper to join them with a semicolon. But they can be very useful when you want to subtly join two related sentences.
My daughter frequently changes her favorite food; right now she likes pancakes.
Note that your sentences are improper and uncommon English grammar. You should separate the final clause of the first sentence with a common, either leaving it as-is or moving it to the first part of the sentence.
Self documenting code is not your thing, I get it.
Note that if you want to use a semicolon, you should definitely move the "I get it" to the first part of the sentence:
I get it, self documenting code is not your thing; this is so obviously homework it hurts.
But such a construct is a bit wordy, and if you really want to join the sentences you'd be better off omitting the aside altogether.
Self-documenting code is not your thing; this is so obviously homework it hurts.