WHAT IS THIS LUMP IN MY ARMPIT?

I'm a 13 year old female, with no family history of cancer. Yesterday I experienced some discomfort in my armpit region. I felt around, and it felt as though there was a pea stuck under my skin. I looked in the mirror, but you couldn't see the lump, just a red sore.
After a few hours, after poking and prodding it quite a bit, it hurt a lot more. It was painful to stretch. I couldn't sleep properly, as I couldn't lie on my side.
The lump is stationary, and can't be moved. It's actually slightly itchy at the moment, though that's probably because I haven't used deodrant due to the fact that I don't want to cause any furthur damage.
I usually shave my armpits with a razor.

[sarah_p]

Solved this problem. Went to the doc, and he said it was a cyst. Cured it with antibiotics

wooo

[I'm the person who asked this lol]

[SassyLassie]

I am glad all is well and that you went to the doc, always a good idea when it involves a lump.  :-)