I doubt if that is it, not at half strength, if that was an issue, there would most likely be some discoloration or burning as well. now is it v'd or more of a curl? are the edges curling upwards and over? with no pic, its hard to tell. by v'd, i mean more like a v shape? watch it and see if it gets worse. post again if there is a problem, someone will help you. be cool.