Originally Posted by MrNick
I'm 5'5'' 120 lbs, if my measurements are correct my chest is about 34'' and my waist is 28''.
I'm about the same size as you (in-fact a bit smaller); unfortunately boys sizes or made-to-measure (or bespoke if you can afford it) are the only options in most cases.
Adults sizes in sweaters or trousers can be fine, and they seem to fit pretty well in your picture, but I find that shirts and coats/jackets are always too big. Shirts especially are very blousy around the waist, and the cuffs are often huge (though that can be addressed by moving the button).