It depends. If you really hate it and have an independent source of income. then go for it.
Otherwise, start looking for another job first, or make sure your savings are up to speed for at least 3-6 months before you pull the trigger.
A job is a job, obviously don't quit cause it looks bad when trying to find another job. Just give them a two week notice or someone before quitting. And find another job before leaving the first one.
That depends. If you have no other means of supporting yourself, you may want to find other employment before quitting. Without more information, it is difficult to give sound advise.
Yes. Nobody loves you.
