In Michigan, it is illegal to chain an alligator to a fire hydrant.
Don't ever tell anyone you were fired or you will never get hired. Just say you quit. It's your word against his if they call him and they might not even do that. Don't ever put you were fired on an application. Never.
Use a short ratan stick, it's not nearly as heavy or as damaging as a baseball bat; it's cheap; and it can be taken everywhere. But this is a temporary solution; you are evidently looking to build up calcium in the shin. That can be done with the bat, since it is heavier, but you shouldn't start with it. In the end, your best bet is to join a kickboxing or fitness gym with a heavy bag you can kick. If you live in an apartment, are there any garages or storage areas you can set up a hanging/standing bag? What about a place you can store a standing bag, but drag it outside somewhere? As to your other problem, they are not healing because you aren't providing enough time to heal. Give a minimum of a week to heal, maybe more if you're in your high 20's or older.