Remember that cats are among the masters of hiding any illness until it's much further advanced than it would ever get if any of we humans felt a bit 'off'.
Laryngitis in a cat may be a symptom of rhinotracheitis and/or calicivirus infection (upper respiratory infections). It could also be ‘feline flu’ (which like ‘kennel cough’ in dogs) or an early symptom of thyroid disease. It could be a reaction to eating something wrong (plant or chemical?), she may have swallowed something that's stuck (although probably not likely) and a large number of other possibilities that need professional, hands-on exam.
In any event, when your companion has any presentation that makes you wonder or causes concern, the peace of mind found in a vet visit that says ‘all’s well’ is priceless!
Isn't it time for a routine visit anyway? Images available only to Customers.
http://www.thecatsite.com/Behavior/44/Cat-Sounds-Feline-Vocal-Communication.html
The link above should also be helpful in guiding you
Many have forgotten this truth, but you must not forget it.
You remain responsible, forever, for what you have tamed.