This is a very difficult question to answer. There are many things that could cause a painful bump or lump underneath the skin in your armpit. It could be an infection, a swollen lymph node, a bacterial infection if you shave your armpit, a fatty growth, cancer or any number of things. Here is a useful website at the National Library of Medicine website Medlineplus on armpit lumps
http://www.nlm.nih.gov/medlineplus/ency/article/003099.htm
The best answer to this is to please try to see a doctor or nurse or get to a health center. Treatment will depend on which of the many relatively harmless or serious conditions that could be causing this bump or lump.
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A pimple, mosquito bite, ingrown hair, or cyst.
A round quarter size bump on top of a child's head could indicate a cyst. Cysts are not painful and are common in children in the head region.
It is most likely a large pimple.
Take your dog to the vet.
You can't say its cancer unless you get it checked by a doctor. some questions to consider is whether the bump changed in size, color and whether the borders are symmetrical or asymmetrical.
Get it checked out by a doctor as it there are a number of causes. It is possible it is a sebaceous cyst, which is very common and easily removed.
You Measure Around You Chest In Inches. Ex: Start With Your Armpit right Underneath your Arm And Measure From There Around Your Chest And Back To The Same Armpit.
Make sure its not an ingrown hair, or go see a doctor. Could be a very poisonous spider bite. just keep an eye on it...
A pea sized bump by the ear is likely to be your lymph node. You have hundreds of them all over your body. They are flat, round and about the size of a pea.
it looks like a bump on ur bak about the size of a golf ballit looks like a bump on ur bak about the size of a golf ball
The company Bump Band manufactures maternity bump bands for women up to size 22. These bands can be added to jeans and skirts to make allowances for a growing baby bump.
If you are sensitive to light and sound, and have blurred vision, you need to go to the hospital. You may have a concussion.
A quarter section of "anything" is one forth of the whole.