Strange lumps on head

I'm 22 years old and I have had a lump on my head for about 10 years; give or take a couple years. It is hard, but if pressed hard enough you can tell it is not bone, though pressure causes some discomfort. It began small and almost unnoticable, but over the last few years it has been increasing in size. Right now it's about the size of a fingernail and maybe 1/4 - 1/2 inch 3D. Also, I just recently noticed that the hair growing out of it is much coarser than the rest of my hair. It is also curly whereas the rest of my hair is very straight. Also, in the last year or so I began to develope two more lumps on my head in addition to the one I've had for years. I'm getting concerned because my balance has been worsening and a couple weeks ago in the grocery store I had a bout of vertigo for just a few seconds. Could these lumps be tumors? Every doctor has said the lump is likely a non-harmful cyst or wen.  

[jujub33ns]

I forgot to mention that the large lump is also very itchy and was not constantly itchy until recently.