right side headlight on very slow

I'm guessing you mean the light is very dim. Light not bright? Try looking for any green corrosion on the connector. Follow the wires back from the headlight and see if you can find a broken or exposed wire that could be grounding out on something. Have you checked out the other bulb? It may be on "HIgh" because the low beam filament has burned out. That would make the bulb your replaced look dim.