This question is probably better asked in the US DM forum. However, I'll answer.
-If your flights are on time, you are fine. There is a bus that connects the 2 terminals.
-There is no guarantee that that 3361 will go to gate 24, so your dilemma might be imaginary.
-If you incoming flight is more than 15-20 minutes, late you might miss it.
-There are many more flights between DCA-CLT and you are arriving early afternoon, there is a very good chance you'll make it at some point later in the day.
-If you end up stuck, the Metro is right outside the airport. You can be at the Capital building in 20 minutes for some impromptu sight seeing.