I don't know if this will help, but it works for me, is cheap and would be worth a try. Wet a clean finger and stick it in some corn starch and then place the finger on the sore/s. Try to keep the area free of saliva for a few seconds or as long as you can. If it works you will notice a difference in 24 hours or less. You might want to reapply two or three times a day until it no longer bothers you. It also works for my husband and two sons, though we do not get multiple sores as you have described. My boss suggested this to me years ago and I thought she was nuts, but now at the first sign of a sore we all apply the corn starch.