Welcome in H.C.M.
In reference to your query injury
of big toe followed by swelling and purple discolouration which initially get improve but lateron swelling reoccured along with sore throat
Bluish discolouration of big toe is due to collection of blood in sub cutaneous resion and recurrence of swelling is due tosecondary infection which if not managed properly than may progress to gangreen.
My advice to consult your surgeon for thorough examination and treatment.