I found a small lump in my left breast, how can I tell if it is just normal breast tissue?

See your doctor. It is very difficult to distinguish normal "lumpy-bumpy" breast tissue from one that warrants further evaluation. Lumps that "count" tend to be 3-dimensionally round rather than pencil- or pancake-shaped and are harder than normal rubbery breast tissue. When finding a new lump, it is best to see your dr.;it may be wise to get a mammogram, ultrasound, or even a biopsy, depending on their findings.
See full answer. Any new finding should be reported to your doctor. Sometimes you can tell by the feel of a lump but generally imaging such as an ultrasound or mammogram is needed; depending on the findings, a needle biopsy might also be recommended. Do not assume that a lump is nothing to worry about if you are young or don't have breast cancer in your family - always get it checked out.