I also believe that it is an irritation. I get bumps and sores in my mouth all the time since its so sensitive from treatments. I also have had a horrible year from my cancer my sister had breast cancer and my mom just had a tumer removed from her lungs. I had a bump by my tongue and it went away. I think that your mouth is just real sensitive right now. I would not worry about it. Actually knowing me I would but I don't think that its anything to worry about it.