I love my little mini but im having problems with her.

Ok, I recently did a DIY rear wiper removal. It was great! But when I removed the wiper I found that it was clogged and there was a water stains all over the interior of the trunk (when i removed the plastic shell). Bottom line is that I think there may be water damage to my boot latch thing. The left license plate light went off and my boot latch wont work at all.
What should I do?
Should I check the fuse box? Or go to a mini dealership? I don't have much money as I'm a college student.

All input would be appreciated Thanks to all

 

Btw its an R53 2002

 

this is an electric latch , there's a switch built in to the rear boot handle as well as the lights for the liscense plate,
I have a chili red handle removed from mine to replace with the carbon fiber one I'd sell for $50

 

Ok, my electric latch doesn't click anymore. So I need to buy a new one? & does the color show?
The only way I can open my trunk is if i hold the unlock button on my key and after 5 secs it opens.