What Causes A Lump In The Throat?

I have a white kind of sticky kind of spot/lump at the back of my throat on the right side in line with my tonsils. It doesn't hurt the only time I can feel it is when I smoke. When I touched it with a cotton bud it didn't hurt it just tingled. I've had it for about 2 weeks now it hasn't got bigger or smaller. Please help I'm really worried.