I'm A 58 Year Old Woman Who Was Put On

I'm a 58 year old woman who was put on Nortriptyline (10 mg/day) about six weeks ago to treat IBS. I started developing acne about two weeks after I began on this prescription (I didn't even have acne when I was a teenager). Nothing else has changed in my diet, exercise, etc.
One other disturbing even that occurred last night was that I felt like I had a bug bite on my chin. I rubbed it for a few minutes and when I looked in the mirror a couple hours later, the skin was removed (almost like peeling the skin off a blister). This has happened to me once before - many years ago - when I was put on Prozac. My doctor took me off of that immediately and I haven't had it happen again until just now. Could the Nortriptyline be the cause?