Gargling a soluble painkiller will help. Sucking on an ice cube too. Pharmacies used to sell Tyrozets (?) which contain anaesthetic and probably very little sugar if any. Worth asking.
Get well soon!
There are sugar free lozenges - i suck Riccola sugar free if Ive got a bad sore throat but more than 3 or 4 in aday they start to impact negatively on my sugars but not as badly as other sugar free drops / boiled sweets that Ive tried
Boots chemist and others stock a mouth spray for dry mouth syndrome Which helps me a lot it's basically a lemon flavour water .also Tring to breathe through nose might help .obviously check incase you have an allergy to any ingredients but it is very basic