I have no idea what I am doing

I joined MFP long ago with a set weight goal in mind AND I REACHED IT!!!!

BUT...

It did not give me the body of my dreams XD

SO now I have realised I am not really sure what I am doing or how to get to what I want.

I'm 5 ft 3 inches and weigh 120lb.

I dont want massive muscles I just want rid of my pot belly and some sort of muscle definition.
Swimming is my main exercise and a lean swimmers physic body without being totally shredded would be my ideal goal.

I thought loosing weight whilst still keeping active with my swimming would give me that but so far not much luck.

Do I just need to carry on and lose more weight? Increase my exercise? do something completly different?