Is a very small bump on the chest a sign of breast cancer? While taking a shower, I noticed a pimple sized red blotch near my chest area. When I squeezed it, some yellow-ish white pus came out, then it bled a little. I freaked out, and I don't know what t

Sebaceous cyst. This sounds like an infected sebaceous cyst which is benign and can occur anywhere on the skin. Please get checked by your dr to make sure it is not a breast lump.
I . I can understand your concern. As this has occurred more than once, please have this evaluated. It sounds like an infectious area such as a small area of a skin infection, but this should be tested and a wound culture taken. It is extremely unlikely that it is cancer, but if you have risk factors and depending on your age it is always wise to get a mammogram. Please see your doctor for evaluation. If you have increased pain, fever, feel flu-like, or have red streaks or increased redness from the area then you must be seen immediately.