I have a question.

I have a question. I kinda didn't do much treatment wise for a few months but I only had it on one toe just a little. Now I have it on two not much on either mostly at the tip. I went thru two bottles of Fungi Gone and I think it helped some. Now I'm using a generic pen I got on Amazon. I've noticed when I use treatment on the original one that was affected,it gets a little sore. This was with both treatments. Anyone else have that