Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services if you or a child is struggling to breathe, has blue or grey lips or skin, cannot speak because of breathlessness, becomes unusually drowsy, or appears to have a blocked airway.
Do not try to inspect or press down the throat when severe breathing or swallowing symptoms are present.
Seek urgent medical help for noisy breathing, drooling, inability to swallow fluids, or rapidly increasing throat or neck swelling.
Arrange a routine medical appointment if your hoarseness is not clearly improving after about two weeks, keeps returning, or affects your ability to work or communicate.
Laryngeal examination is generally recommended if a voice change continues for four weeks.
The article also says
Seek earlier assessment if you have:
A neck lump
Pain or difficulty when swallowing
Pain when speaking that does not settle
Coughing up blood
Unexplained weight loss
Hoarseness after neck surgery or placement of a breathing tube
A history of smoking with a persistent voice change
Sudden major voice loss after shouting, singing, or other forceful voice use
Every sign above is quoted from the sofidex article on Laryngitis. If you are not sure, err upward — it is always reasonable to be checked.