I know plane tickets are more expensive last minute (month in advance as opposed to several) but how much more?
Should I tell anyone where I am going? They will probably judge me and tell me I am wasting my money and why would you want to go have a life kind of cr@p.
You could always head to Florida, there's a lot on your list that you can check off there. You can check out St. Augustine, the oldest continuously occupied European-established settlement and port in the continental United States (there's your history). Then you can head down to a beach like Daytona, stay somewhere along the beach (I stay at Hawaiian Inn Beach Resort during surfing trips) close to the pier so you can go fishing. Then if you're feeling up to it, drive down south and take an airboat tour in the Everglades. It's all a great time, and I think you'll like the people you meet.
As far as telling people goes, do whatever YOU want to do. If they're not paying for it, why does it matter to them?
If you have long vacation try Nepal where you can find lots of historical places and Mustang (Nepal) for exotic nature. Try the following link for images
New Orleans is a great city with lots of history.
Belize would be a good vacation for the things you're looking for. http://www.travelbelize.org/ Ratheryou tell anyone or not is totally up to you. It's your vacation; why would you care what other people think of it?
You can come our country to travel. We have the world largest sea beach all over the world. we have largest mangrove forest.