It's up to you, of course. Keep in mind that the fillings released mercury into your body, and that poison will stay there forever unless you remove it.
Fatigue and hair-loss are common symptoms of mercury toxicity, but you may have others you don't realize are caused by the metal. If you haven't already, I would do a search for common symptoms of heavy metals and see if you have any more. I had a lot of health problems which I didn't realize were connected until they started going away with chelation.
Chelating is a long slow process, but it's well worth it for the sake of your long term health. Filling replacement is a necessary first step, but it's only the first step. It likely won't make you feel better unless you get the metal out too.