Good that the problem has gone away, but as suggested you do need to check to see if you can find the cause of the original problem.
There will most likely be evidence of shorting water damage (water marking) or even carbon tracking (black marks caused by the spark associated with the short). Note though if it was earth leakage sparking would be minimal.
Not suggesting that you get someone in to check but there are things that you can do yourself. While the caravan is completly disconnected from 240V power (including inverters, generators etc) visually inspect behind each power point for signs of water / metal / conductive material that may have contacted the wires and power points. Also make sure that wires are not loose.
If a circuit breaker / RCD (earth leakage) trips with all items removed from power points then the issue is generally between the CB/RCD and the power points being protected. In the case of a caravan with one CB/RCD this would mean all power points are suspects.
I have had an issue explained to me about neighbours earthing being incorrect and triggering RCD on other houses but do not have the details and believe it is a rare event.
If you have access to a plug in power meter (or current meter) check to see that with all power points off and all appliances disconnected that there is no power (current draw) being used by the caravan. In some cases associated with water entry (and other shorts) it is possible that the short has now dried out and is only drawing small amounts of current (again not a frequent occurance but could explain why it is working now)
Another test is while everything is working, use a single appliance (not electronic) and plug it into each power point and check that all power points are working (hair dryer, kettle) remove as many appliances as possible.
Once all power points are checked then plug each item in the caravan in one at a time, check and then turn off and remove plug and move on to next. With the fridge make sure it is on 240V.
If any power point or appliance trips then you have isolated the problem and can get it fixed.
Then finally plug fixed items in and run together. If there is an issue here then check all combinations and determine which combination gives the failure. You may need help here if it is a combination issue. (Good idea to check with a power meter (current meter) that you have not exceeded the 15 Amps).
Hope this helps.