asking for a friend...

so I had my period December 25 and that lasted 7 days..come January my period was late 9 days which I eventually got it super light with no clots passing, I wasn't bleeding enough to use a pad. I had been experiencing breast soreness and feeling tired. I did take a pregnancy a couple days after my period was due it came out negative then I took one after I bled and came out negative...could there be another reason why my breasts are still sore and I feel pressure in my lower belly