Hi,
Take some stem inhalations, drink plenty of warm water so that keeps the mucosa hydrated and also reduces the inflammation and swelling. Voice rest for few days also will definitely help you. In case if your symptoms does not improve please do consult your ENT specialist.
Regards
OHNS
Hard to say, Andy, not a lot of information there. This could be something benign and self-limited like a viral laryngitis or some vocal abuse. This just requires time, keeping quiet and drinking fluids. Other, less common and possibly more serious possibilities exist. You should see a doctor if it doesn't get better.