Hello Sandra,
This equation is a tricky one. In any case, my recommendation is based on limited
budget and desired unlimited experience.
If, as declared in your preamble, you own the 18-55mm, then the next step would
consider enlarging your experience in either direction: wider lenses or telephoto lenses.
This is how complicated your options are: going wider or further! Seen this way, you
don't need help really… Look around, this forum has plenty of pictures and you will find
what attracts you the most: going wider or further!
Sandra, whichever, come back with some cool takes you will have done exploring this
new experience…
Have a good time!