My boobs feel bruised?

Lately I have been having super sore boobs! They feel almost bruised and heavy feeling. My period is due in about a week and they have been hurting for about a week also. This isn't a typical PMS symptom I have, does anyone else know any likely causes and ways to help them feel better? (Also I am ttc so I'm wondering if this could possibly be an early pregnancy symptom?) Thank you! ☺️