Also, one other thing to keep in mind is that these things can actually produce a vapor that is hotter than what you may or may not have been used to smoking regular ciggies. Couple that with high nicotene mg, and if you have any sort of sensitivity, then a mouth sore isn't all that unlikely, and I would imagine that the 0nic although helped dramatically - you were about at the end of the lifespan for your sore also.
My .02 anyway!
C-ME!
- Hap
My .02 anyway!
C-ME!
- Hap