Shit and Bitch are two words used most commonly in informal communication. While both words can be used derogatorily, they carry significantly different connotations.
Shit is often used as an expression of frustration or anger about a situation. It is not necessarily directed at or about a person, and is not necessarily a sign of disrespect. It is more of an emotional or reactive word.
Bitch is usually a term used to describe a person. It is often meant to be negative and insulting, or used in anger towards and individual. It usually indicates that someone has displayed bad behavior that warrants the use of the term.
In conclusion, Shit and Bitch are two words that are used differently in our society. While both are used as slang and often mean the same thing, connotations, usage, and targets of these words are very different