Is coughing out blood or having chest pains a sign of breast cancer?

Call doc now : This probably is not a sign of breast cancer, but still could be a sign of a serious medical condition. You need to be examined by a doctor immediately. Go seek care in an emergency department if this is happening to you.

It is a sign alright: It is a sign of nothing good. Get it checked out by a physician. Without also having a size able lump in your breast or a past history of breast cancer, i think it is rather unlikely that these are signs of breast cancer, however.