I'm 20 years old, and recently I had a wart on my finger. I tried treating it with the Dr. Scholl's one step system (the pads with the salycillic acid) and it is still there. Maybe I didn't do it long enough?

It seems also to be spreading, since I have two more starting on my hand as well as one large one on my foot.

What could be causing this? And is there anything I can do short of making a doctor's appointment?