I have a lump and dimple on my jaw -- appt. w/ doc in a couple of days. Cancer?

I know lumps w/ dimples in are deemed cancerous because the lump is considered rooted to deeper tissue. My doc prescribed me antibiotics, and the lump has reduced in size, however, it has hit a plateau and now a dimple has formed over it and it appears bruised. The lump is move-able and not painful. Wondering if anyone could share similar experiences.