Am I ready to move down in size?

I started surfing about 2 years ago. I am currently 19 and live in Los Angeles. I surf local breaks like El Porto, Doc, H.B. & Malibu. I started on an Epoxy long board. I moved down in size to a fish. The fish is limiting my ability to pull a smooth bottom or top turn with the wide swallow tail. I was wondering what your thoughts were on me moving down to a dumpster diver, gun/thruster? I do not think it is too fast too soon. I have ridden a couple friends boards but wanted a second opinion.