Susan,
if you are in a room say downstairs under the ensuite within your home and you are able to hear a noise that sounds like a drip or drop of water
then can i suggest that the last of the water from the cistern of your toilet has not stopped flowing and that it takes the time for the cistern
to fill fully and then shut down before the noise stops.
one of the ways to check this is to put a tissue on the wall of the toilet bowl, up high near the top rim and see if this tissue gets wet.
You will need to flush the toilet, wait for the nosie to stop and then apply the tissue or even your fingers laid flat on the bowl will do the
same for you. If the tissue or your fingers get wet then the cistern needs some attention, like washers changed or outlet valve checked
for distortion, I am sure that your local plumber would be able to assist.in fixing the problem.
All the best to you
Colin