I feel sorry for you, but unfortunately your post indicates your inexperience in traveling. Hopefully you will learn from the experience.
1. Seriously consider travel insurance. It would have paid almost all your trip delay expenses.
2. Always carry a change of clothes (or two) in your carry on.
3. Never check anything valuable. I would never have $2,500 of "stuff" in my checked luggage. Period. Either carry on or ship it insured through a courier.
4. Not sure about your shower issues. You should have had a shower the morning that you checked out of your hotel that Delta gave you. 2am to bed, 8am up, shower, 8.30-9am leave for airport for 11am flight. ("I hung out all day in a small town without a shower or clean clothes"). It must have been your choice to not have taken a shower that morning, i.e. sleep longer vs. take a shower. I can't fault the airline for that.
5. Not sure why the $160 car parking fee is mentioned - the car parking fee would have been one extra day due to your delay, certainly not $160 extra.
When all is said and done, I would write Delta through the Contact Us feature on the website. Be much more concise than your initial post here and don't include irrelevant parts like $160 for parking and no shower (your choice). Explain what happened, what you did to try to resolve the problem, what your expenses were and what you would like in compensation. Even with no status, they should do something for you.