welcome to healthcare magic ! i understand your concern. from your post it appears that you have been very harsh on our tongue applying a lot of pressure and the whitening toothpaste. The whitening toothpastes mostly contain hydrogen peroxide
which may damage the oral mucosa
if used concentrated. The same reason could be for your sore throat
. Another reason for all these symptoms could be a bacterial or viral infection since you have swollen glands also. Please apply Mocopain and Hexigel ointments
alternatively on the tongue. Use Betadine gargles twice or thrice a day for sore throat and you can also take antibiotics in case there is some throat infection
. please go for a complete oral examination. Please do not panic about cancer. The doctors will advise the course of treatment and rule out cancer if they feel the need. Take care and all the best!