What Causes Tender Breasts Along With Delayed Periods And Stomach Aches?

Hi i was wondering if anyone could answer this for me:- • I have very sore and tender breasts • I have a very late period • Lower stomach pains • Done pregnancy tests that have come back negative • Lower and Higher Back Pain • Constantly feeling sick • Been getting frequently tired and exhausted • White Spots have been noticed on my breast by my fiancé • My lower stomach and surrounding areas are extremely hard all the time but seem to get alot harder after food • I have had some strange food ideas that I have recently really started to like e.g Mayonaise in Curries and Chilli Could I be pregnant?