Advice plss x

My breasts have been extremely sore & sensitive now for about 3 weeks, they were sore before I was due on my period which I considered normal (I then had some bleeding which was bright red, however didn’t last as long & not painful which is strange for me as my periods are usually horrendous) the sore breasts continued through the time I bled and got worse after this bleeding, still very sore now. I’ve taken a test but it was a clear negative. I thought that was my period but I’m just not sure. Anyone experience sore breasts before outside of their cycle for this long? Or had a similar experience / late BFPs?