I agree wholeheartedly - check the voice with ENT specialist, then if given the all-clear find a good voice trainer.

I have a problem with a crappy throat & after a particularly bad year of infections last year sore (sorry!) a specialist. My problem was that I had started to use the wrong muscles & eventauly after so long had to learn to use the right ones.

Still get the bad throats, but at least the therapist taught me how not to use bad technique.

Good luck, maybe just sing more blues.