I hear you about the voice changes as I probably sound like Mickey Mouse now compared to my former self. It could be anything just using myself as an example, like the cold winter air/wind on your throat, straining voice to be heard, talking too much, dry mouth, mucus, spicy food, sips of alcohol, and effects of radiation all effected my speech/throat.

As it goes, any unusual sign or symptom lasting more than 2-3 weeks, I often waited less, should be looked into by your doctors, more likely your ENT, who may do a flex scope of your throat or perform other evaluations. During mine a few years ago, my ENT found I have a paralyzed left vocal cord, which effects my voice. As such, I was sent twice to "voice specialists", actually otolaryngologists who specialize in voice and others disorders, who can do vocal cord injections with collagen, other material, to strengthen the voice, but I never had them done.

Instead, I was sent to Speech and Language Pathologists, SLP, for swallow boot camp where I was evaluated, and had a modified barium swallow study done, about my 3rd or 4th, where it was showed again my epiglottis doesn't fully close, and silently aspirate, so I had exercises to do, and shown what swallow maneuvers helped that, and to strengthen my voice,

I hope this helps.