Purple lump on breast, what do I do?

I am thinking it is a cyst. Several weeks ago it started as a lump that I thought was a pimple. I squeezed it and I think it caused bruising. It was a big lump that everntually flattened but stayed purple. It eventually faded to a light purple and I thought it was going away.

I took off my bra after a long day today and it is swollen and purple. I tried squeezing it (To which I regret) and It is super swollen and painful. I'm so embarassed...